US7750359B2 - Package design for producing white light with short-wavelength LEDS and down-conversion materials - Google Patents

Package design for producing white light with short-wavelength LEDS and down-conversion materials Download PDF

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US7750359B2
US7750359B2 US11/795,171 US79517106A US7750359B2 US 7750359 B2 US7750359 B2 US 7750359B2 US 79517106 A US79517106 A US 79517106A US 7750359 B2 US7750359 B2 US 7750359B2
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light
wavelength
short wavelength
broad bandwidth
quantum dot
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Nadarajah Narendran
Yimin Gu
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Rensselaer Polytechnic Institute
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L33/00Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L33/48Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
    • H01L33/50Wavelength conversion elements
    • H01L33/501Wavelength conversion elements characterised by the materials, e.g. binder
    • H01L33/502Wavelength conversion materials
    • H01L33/504Elements with two or more wavelength conversion materials
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B82NANOTECHNOLOGY
    • B82YSPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y10/00Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/59Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing silicon
    • C09K11/592Chalcogenides
    • C09K11/595Chalcogenides with zinc or cadmium
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/64Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing aluminium
    • C09K11/641Chalcogenides
    • C09K11/642Chalcogenides with zinc or cadmium
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/77Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
    • C09K11/7766Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing two or more rare earth metals
    • C09K11/7774Aluminates
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09KMATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/77Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals
    • C09K11/7766Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing rare earth metals containing two or more rare earth metals
    • C09K11/7777Phosphates
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00Electroluminescent light sources
    • H05B33/12Light sources with substantially two-dimensional radiating surfaces
    • H05B33/14Light sources with substantially two-dimensional radiating surfaces characterised by the chemical or physical composition or the arrangement of the electroluminescent material, or by the simultaneous addition of the electroluminescent material in or onto the light source
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02BCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps

Definitions

  • the present invention concerns solid-state white light emitting devices.
  • these devices and methods use a short wavelength light source with both phosphor and quantum dot down conversion materials.
  • Solid state light emitting devices including solid state lamps having light emitting diodes (LED's) and resonant cavity LED's (RCLED's) are extremely useful, because they potentially offer lower fabrication costs and long term durability benefits over conventional incandescent and fluorescent lamps. Due to their long operation (burn) time and low power consumption, solid state light emitting devices frequently provide a functional cost benefit, even when their initial cost is greater than that of conventional lamps. Because large scale semiconductor manufacturing techniques may be used, many solid state lamps may be produced at extremely low cost.
  • LED's light emitting diodes
  • RCLED's resonant cavity LED's
  • LED's have found considerable application in indoor and outdoor informational displays.
  • An exemplary embodiment of the present invention is a method of producing visible light using a short wavelength solid state light emitting device, a quantum dot material and a phosphor material, where the visible light has a chromaticity value near the blackbody locus and a color rendering index greater than about 80.
  • Short wavelength light having a first spectrum with a first peak wavelength is generated using the short wavelength solid state light emitting device.
  • the first peak wavelength is shorter than about 500 nm.
  • the quantum dot material is irradiated with at least a portion of the short wavelength light such that a first fraction of the short wavelength light is absorbed and reemitted by the quantum dot material as long wavelength light having a second spectrum with a second peak wavelength.
  • the second peak wavelength is longer than about 600 nm.
  • the phosphor material is irradiated with at least a portion of the short wavelength light such that a second fraction of the short wavelength light is absorbed and reemitted by the phosphor material as mid wavelength light having a third spectrum with a third peak wavelength.
  • the third peak wavelength is between the first peak wavelength and the second peak wavelength.
  • a third fraction of the short wavelength light, at least a portion of the mid wavelength light and at least a portion of the long wavelength light are emitted as the visible light.
  • Another exemplary embodiment of the present invention is a broad bandwidth light source including: a short wavelength solid state light emitting device; a quantum dot material optically coupled to the short wavelength solid state light emitting device to be irradiated by a first portion of the short wavelength light; and a phosphor material optically coupled to the short wavelength solid state light emitting device to be irradiated by a second portion of the short wavelength light.
  • the short wavelength solid state light emitting device generates short wavelength light having a first spectrum with a first peak wavelength that is shorter than about 500 nm.
  • the quantum dot material is adapted to absorb a fraction of incident light having the first spectrum and reemit it as long wavelength light having a second spectrum with a second peak wavelength that is longer than about 600 nm.
  • the phosphor material is adapted to absorb a fraction of incident light having the first spectrum and reemit it as mid wavelength light having a third spectrum with a peak wavelength that is between the first peak wavelength and the second peak wavelength.
  • the short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that some of the short wavelength light, some of the long wavelength light, and some of the mid wavelength light are emitted substantially coincidentally from the broad bandwidth light source as a visible light having a chromaticity value near the blackbody locus and a color rendering index greater than 80.
  • a further exemplary embodiment of the present invention is a broad bandwidth light source for producing visible light having a chromaticity value near a blackbody locus and a color rendering index greater than about 80.
  • the broad bandwidth light source includes: means for generating short wavelength light having a first spectrum with a first peak wavelength; means for absorbing and reemitting a first fraction of the short wavelength light as long wavelength light having a second spectrum with a second peak wavelength; and means for absorbing and reemitting a second fraction of the short wavelength light as mid wavelength light having a third spectrum with a third peak wavelength.
  • the first peak wavelength is shorter than about 500 nm
  • the second peak wavelength is longer than about 600 nm
  • the third peak wavelength is between the first peak wavelength and the second peak wavelength.
  • a third fraction of the short wavelength light, at least a portion of the mid wavelength light, and at least a portion of the long wavelength light are emitted as the visible light.
  • FIG. 1 is a cut away side plan drawing illustrating an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention
  • FIG. 2 is a graph illustrating exemplary spectra of a blue light emitting diode, a yellow/green phosphor material, and a red quantum dot (QD) material;
  • FIG. 3A is a graph illustrating the spectrum of an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention.
  • FIG. 3B is a CIE-1931 diagram illustrating the color characteristics of an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention
  • FIG. 4 is a cut away side plan drawing illustrating another exemplary broad bandwidth light source according to an exemplary embodiment of the present invention.
  • FIG. 5 is a cut away side plan drawing illustrating a further exemplary broad bandwidth light source according to an exemplary embodiment of the present invention
  • FIG. 6 is a flowchart illustrating an exemplary method of producing visible light having a chromaticity value near a blackbody locus and a color rendering index greater than about 80 according to an exemplary embodiment of the present invention
  • FIGS. 7A and 7B are schematic block diagrams illustrating exemplary methods of producing visible light using a short wavelength solid state light emitting device, a QD material, and a phosphor material according to an exemplary embodiment of the present invention.
  • FIG. 7C is a schematic block diagram illustrating an exemplary method of producing visible light using a short wavelength solid state light emitting device and a combined QD/phosphor material according to an exemplary embodiment of the present invention.
  • this method has a drawback in that the light produced has a spectrum with a very high correlated color temperature (CCT) and may have poor color rendering properties, especially in the red region.
  • CCT correlated color temperature
  • SPD spectral power distribution
  • Quantum dots are nanometer size semiconductors that have the property of absorbing energy in one spectral range and emitting energy in another spectral range.
  • One of the unique features of QD's that may make them interesting in solid-state lighting applications is that the absorption and emission spectra of a QD are related to the average physical size of the QD particle. Therefore, by controlling the diameters of the QD's in a material, theoretically, a material that may produce a tailored, continuous emission spectrum from a narrow bandwidth source may be achieved.
  • Cadmium selenide-based (CdSe) QD's can be tuned to emit radiation across the entire visible spectrum range (380 nm to 780 nm). Therefore, it is contemplated that CdSe-based QD's are a potential down-conversion material for use in white LED applications. Because the peak wavelength of the emission spectrum of QD's is proportional to their average diameters, it may be possible to combine QD's of different diameters to produce an almost continuous spectrum white light when excited by an ultraviolet or blue LED.
  • the inventors have tested solid state lighting devices in which red CdSe quantum dots (QD's) (620 nm) have been layered around a blue GaN LED. These tests produced a light source with an output color that is purplish blue and a low luminous efficacy. These results are caused by the lack of output energy by these devices in the green-yellow spectral region.
  • QD's red CdSe quantum dots
  • Exemplary embodiments of the present invention include devices and methods to produce white light that may mimic sunlight using light emitting diodes (LED's) and down-conversion materials. These exemplary embodiments use high efficiency red QD's and yellow-green phosphor as down-conversion materials. Hence, the package luminous efficacy may be increased while maintaining the desired chromaticity value.
  • LED's light emitting diodes
  • down-conversion materials include high efficiency red QD's and yellow-green phosphor as down-conversion materials.
  • FIG. 1 illustrates exemplary broad bandwidth light source 100 according to an exemplary embodiment of the present invention.
  • Exemplary broad bandwidth light source 100 includes: short wavelength solid state light emitting device 102 to generate short wavelength light; QD material 104 ; and phosphor material 106 , all of which are mounted on optical mount 108 .
  • Optical mount 108 provides mechanical support and may also act as a heat sink to help dissipate heat generated by the short wavelength solid state light emitting device 102 and the down-conversion materials.
  • Optical mount 108 may also have a reflective coating to increase emission of the visible light out of the top surface of exemplary broad bandwidth light source 100 .
  • the positions of QD material 104 and phosphor material 106 shown in FIG. 1 may be desirable, other configurations of these two material layers may be used in exemplary embodiments of the present invention.
  • the positions of QD material 104 and phosphor material 106 may be exchanged in the exemplary embodiment of FIG. 1 .
  • Exemplary broad bandwidth light source 100 addresses the lack of green-yellow light in the spectrum of the experimental solid state light source described above by creating a packaging concept that couples both red QD's and yellow-green phosphor as down-conversion materials with a solid state blue or UV light source.
  • short wavelength solid state light emitting device 102 may be embedded within QD material 104 and phosphor material 106 may be layered on top the QD material layer.
  • FIGS. 7A-C schematically illustrate operation of exemplary broad bandwidth light sources.
  • all photons (arrows) are shown propagating forward.
  • down-converted photons may be radiated in all directions and the photons of short wavelength solid state light emitting device 102 may not be collimated as shown in FIGS. 7A-C .
  • short wavelength photons are represented by arrows marked B
  • mid wavelength photons are represented by arrows marked G
  • long wavelength photons are represented by arrows marked R.
  • photons 700 represent the short wavelength photons generated by short wavelength solid state light emitting device 102 .
  • photons 700 are incident on phosphor material 106 and some of them are absorbed by phosphor material 106 and reemitted as mid wavelength photons.
  • Photons 702 include non-absorbed, short wavelength photons (B) that are transmitted through phosphor material 106 and emitted mid wavelength photons (G).
  • Photons 702 are incident on QD material 104 .
  • Some of remaining short wavelength photons and some of the mid wavelength photons are absorbed by QD material 104 and reemitted as long wavelength photons.
  • the remaining short wavelength photons and the remaining mid wavelength photons (G) are transmitted through phosphor material 106 and combine with the emitted long wavelength photons (R) to produce broad bandwidth light 704 .
  • photons 700 are incident on QD material 104 and some of them are absorbed by QD material 104 and reemitted as long wavelength photons. The remaining short wavelength photons are transmitted through QD material 104 .
  • Photons 706 include non-absorbed, short wavelength photons (B) that are transmitted through QD material 104 and emitted long wavelength photons (R). Photons 706 are incident on phosphor material 106 . Some of remaining short wavelength photons are absorbed by phosphor material 106 and reemitted as mid wavelength photons. The remaining short wavelength photons (B) and the long wavelength photons (R) are transmitted through phosphor material 106 and combine with the emitted mid wavelength photons (G) to produce broad bandwidth light 704 .
  • photons 700 are incident on combined QD/phosphor material 402 and some of them are absorbed by combined QD/phosphor material 402 and reemitted as mid wavelength photons and long wavelength photons.
  • the remaining short wavelength photons (B) are transmitted through combined QD/phosphor material 402 and combine with the emitted mid wavelength photons (G) and the long wavelength photons (R) to produce broad bandwidth light 704 .
  • exemplary broad bandwidth light source 100 may produce an almost continuous spectrum of visible light. As a result, both the chromaticity value and luminous efficacy of exemplary broad bandwidth light source 100 may be improved.
  • CRI color rendering index
  • CCT correlated color temperature
  • FIG. 2 illustrates spectral graph 200 , which includes three spectra.
  • Spectrum 202 represents the spectrum of the short wavelength light generated by an exemplary short wavelength solid state light emitting device 102 .
  • Spectrum 204 represents the spectrum of the mid wavelength light emitted by an exemplary phosphor material 106 .
  • Spectrum 206 represents the spectrum of the long wavelength light emitted by an exemplary QD material 104 .
  • the relative amounts of light from each of these spectra may be controlled to produce a visible light with desired optical properties such as chromaticity, CRI, and CCT.
  • Spectral graph 300 in FIG. 3A illustrates exemplary combined spectrum 302 that may be produced in this manner.
  • the chromaticity value of the emitted light may be changed.
  • the chromaticity value of the emitted light may also be changed by choosing a short wavelength solid state light emitting device, a QD material, and/or a phosphor material that have different spectra than those shown in FIG. 2 .
  • a chromaticity near the black body locus has been found to be most natural to people and, thus, preferred for lighting designs.
  • FIG. 3B shows CIE-1931 diagram 304 on which spectrum locus 306 , black body locus 308 , and chromaticity value 310 of exemplary combined spectrum 302 shown in FIG. 3A have been plotted.
  • chromaticity value 310 of exemplary combined spectrum 302 shown in FIG. 3A is very near to black body locus 308 .
  • Proper selection and configuration of short wavelength solid state light emitting device 102 , QD material 104 , and phosphor material 106 may allow the chromaticity value of the visible light emitted from broad bandwidth light source 100 to be desirably set within an area bounded by about 0.01 of the x chromaticity value and about 0.01 of the y chromaticity value of the blackbody locus on a CIE-1931 diagram.
  • CRI is a figure of merit, on a scale of 0 to 100, used by manufacturers of fluorescent, metal halide and other nonincandescent lighting equipment to describe the visual effect of the light on colored surfaces.
  • Natural daylight and any light source approximating a blackbody source are assigned a CRI of 100.
  • the CRI defines the spectral transmissive quality of glasses or other transparent materials. In this case, values of 95 or better are considered acceptable for allowing true color rendering.
  • Typical cool white fluorescent lamps have a CRI of approximately 62. Fluorescent lamps having rare-earth phosphors have achieved CRI's of 80 and above.
  • the CRI of a typical white LED based on a blue LED and YAG phosphor is between 70 and 78.
  • Proper selection and configuration of short wavelength solid state light emitting device 102 , QD material 104 , and phosphor material 106 may allow the CRI of the visible light emitted from broad bandwidth light source 100 to be desirably set to be greater than about 85 or even greater than about 90.
  • Short wavelength solid state light emitting device 102 generates short wavelength light that desirably has a peak wavelength shorter than about 500 nm, for example between about 200 nm and about 500 nm.
  • the solid state light emitting device may be a light emitting diode (LED), a resonant cavity LED, or a diode laser.
  • LED light emitting diode
  • Examples of materials from which these devices may be formed include: InGaN; GaN; SiC; GaN on a SiC, and other semiconductor materials.
  • QD material 104 is optically coupled to short wavelength solid state light emitting device 102 so that it may be irradiated by a portion of the short wavelength light.
  • QD material 104 is shown to surround short wavelength solid state light emitting device 102 .
  • This is not necessary, however, as long as QD material 104 is sufficiently irradiated with the short wavelength light.
  • Providing space between QD material 104 and short wavelength solid state light emitting device 102 may be desirable to reduce optical coupling of short wavelength light emitted by QD material 104 into short wavelength solid state light emitting device 102 . Such ‘back coupling’ of longer wavelength light may lead to undesirable heating of short wavelength solid state light emitting device 102 .
  • QD material 104 is adapted to absorb a fraction of incident short wavelength light and to reemit the absorbed light as long wavelength light having a peak wavelength that is longer than about 600 nm, for example between about 600 nm and about 700 nm.
  • the full width half maximum (FWHW) of the spectrum of the long wavelength light emitted by QD material 104 may be less than about 50 nm, although in some applications a broader spectrum of long wavelength light may be desirable.
  • a broader spectrum of long wavelength light may be particularly desirable if a component of infrared light is to be added to the visible. It is noted that a small contribution of infrared light to visible light has been found to have beneficial psychological and physical effects for some people.
  • QD material 104 includes a large number of QD's that are dispersed within a matrix material.
  • This matrix material is desirably substantially transmissive to the visible light being produced by broad bandwidth light source 100 .
  • the matrix material may include: UV curable clear resin; thermal curable sol-gel resin; UV curable sol-gel resin; polycarbonate; polystyrene; polymethyl methacrylate (PMMA); polyethylene; various epoxies; silicones; silica; or titania.
  • the QD's typically have a diameter in range of about 1.9 nm to about 10.0 nm, although this range is not limiting, and may be formed of any standard QD material, such as CdSe, ZnS, PbSe, CdTe, PbTe, ZnSe, Si, or Ge, among others.
  • Phosphor material 106 is adapted to absorb a fraction of incident short wavelength light and to reemit the absorbed light as a mid wavelength light having a peak wavelength between the peak wavelength of the short wavelength light and the peak wavelength of the long wavelength light, often desirably between about 500 nm and about 600 nm.
  • the full width half maximum of the spectrum of the mid wavelength light emitted by phosphor material 106 may be less than about 150 nm, depending on the specific phosphor used.
  • Phosphor material 106 may includes a large number of phosphor particles that are dispersed within a matrix material. As with the matrix material of QD material 104 , this matrix material is desirably substantially transmissive to the visible light being produced by broad bandwidth light source 100 and may include, for example: UV curable clear resin; thermal curable sol-gel resin; UV curable sol-gel resin; polycarbonate; polystyrene; polymethyl methacrylate (PMMA); polyethylene; various epoxies; silicones; silica; or titania. Alternatively, phosphor material 106 may be a bulk phosphor material, possibly formed into a flat substrate as shown in FIG. 1 .
  • the phosphor particles or the bulk phosphor material may include at least one standard yellow or green phosphor, such as: ZnS:Cu—Al; ZnSiO 4 :Mn 2+ ; Sr 3 SiO 5 :Eu 2+ ; BaMgAl 10 O 17 :Eu 2+ Mn 2+ ; SrAlO 4 :Eu,Dy; (YGdCe) 3 Al 5 O 12 :Eu; Sr 4 Al 14 O 25 :Eu; (Ce, Tb)MgAl 11 O 19 ; or (La, Ce, Tb)PO 4 , YAG:Ce, or other phosphors.
  • standard yellow or green phosphor such as: ZnS:Cu—Al; ZnSiO 4 :Mn 2+ ; Sr 3 SiO 5 :Eu 2+ ; BaMgAl 10 O 17 :Eu 2+ Mn 2+ ; SrAlO 4 :Eu,Dy;
  • Exemplary broad bandwidth light source 100 illustrated in FIG. 1 is configured such that the short wavelength light with which phosphor material 106 is irradiated has first been transmitted through QD material 104 before it is incident on the phosphor material.
  • the positions of QD material 104 and phosphor material 106 may be reversed, the configuration shown in FIG. 1 may provide an advantage.
  • ‘back coupling’ of light into short wavelength solid state light emitting device 102 may lead to undesirable heating.
  • QD material 104 is adapted to absorb and reemit a fraction of the incident mid wavelength light as well as a fraction of the short wavelength light, the configuration shown in FIG. 1 may desirably reduce the amount of mid wavelength light that is back coupled into short wavelength solid state light emitting device 102 .
  • FIGS. 4 and 5 illustrate alternative exemplary broad bandwidth light sources 400 and 500 , respectively.
  • Each of these alternative exemplary broad bandwidth light sources includes a combined QD/phosphor material.
  • This combined QD/phosphor material includes a plurality of QD's and a plurality of phosphor particles that are dispersed within a matrix material that is substantially transmissive to the visible light of the exemplary broad bandwidth light source.
  • the QD's and the phosphor particles may be dispersed separately in specific regions of the matrix material, or they may be mixedly dispersed within the matrix material.
  • FIG. 4 illustrates exemplary broad bandwidth light source 400 in which combined QD/phosphor material 402 is formed surrounding short wavelength solid state light emitting device 102 .
  • FIG. 5 illustrates exemplary broad bandwidth light source 500 in which combined QD/phosphor material 502 is formed on the surface of optical element 504 .
  • Optical element 504 may desirably be a light guide that may help to reduce back coupling of mid and long wavelength light from combined QD/phosphor material 502 into short wavelength solid state light emitting device 102 .
  • An exemplary broad bandwidth light source according to the exemplary embodiment of FIG. 1 was formed using a GaN-based bare blue LED device as short wavelength solid state light emitting device 102 .
  • This blue LED was immersed in a layer of red QD's that had a peak emission wavelength of 630 nm (QD material 104 ) and a YAG yellow/green phosphor layer (phosphor material 106 ) was placed in front of the LED and QD material.
  • QD material 104 a peak emission wavelength of 630 nm
  • phosphor material 106 a YAG yellow/green phosphor layer
  • Measurements of this exemplary device show that the package luminous efficacy was 211 m/W, which is close to that of a corresponding commercially available white LED device which uses a phosphor only down conversion material (231 m/W).
  • the exemplary broad bandwidth light source which produced the exemplary data shown in FIGS. 3A and 3B , had a CRI of 90 with a chromaticity value close to the blackbody locus.
  • the inventors were able to demonstrate an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention that achieves superior color quality with a minimal reduction of luminous efficacy.
  • FIG. 6 illustrates an exemplary method of producing visible light using a short wavelength solid state light emitting device, a QD material, and a phosphor material.
  • the visible light produced by this exemplary method has a chromaticity value near the blackbody locus and a CRI greater than about 80.
  • This method may desirably use any of the exemplary broad bandwidth light sources described above with reference to FIG. 1 , 4 , or 5 .
  • Short wavelength light is generated using the short wavelength solid state light emitting device, step 600 .
  • the short wavelength light has a first spectrum with a peak wavelength that is desirably shorter than about 500 nm.
  • the QD material is irradiated with at least a portion of the short wavelength light such that a fraction of the short wavelength light is absorbed and reemitted by the QD material as long wavelength light, step 604 .
  • the long wavelength light has a second spectrum with a peak wavelength which is desirably longer than about 600 nm.
  • the phosphor material is also irradiated with at least a portion of the short wavelength light such that a fraction of the short wavelength light is absorbed and reemitted by the phosphor material as mid wavelength light, step 602 .
  • the mid wavelength light has a third spectrum with a peak wavelength between the peak wavelengths of the short wavelength light and the long wavelength light.
  • a remainder of the short wavelength light, at least a portion of the mid wavelength light, and at least a portion of the long wavelength light are emitted from the as exemplary broad bandwidth light source the visible light, step 606 .
  • the QD material may be irradiated with at least a portion of the mid wavelength light in addition to the short wavelength light.
  • a fraction of the mid wavelength light may be absorbed and reemitted by the QD material as additional long wavelength light, step 608 .

Abstract

A broad bandwidth light source including: a solid state light emitting device that generates short wavelength light; and quantum dot material and phosphor material that are each irradiated by some of the short wavelength light. The short wavelength light has a spectrum with a first peak wavelength shorter than about 500 nm. The quantum dot material absorbs some of the short wavelength light and reemits it as long wavelength light having a spectrum with a second peak wavelength longer than about 600 nm. The phosphor material absorbs some of the short wavelength light and reemits it as mid wavelength light having a spectrum with a peak wavelength between the first and second peak wavelength. The light source is configured such that some of each light (short, mid, and long wavelength) is emitted coincidentally as a light having a chromaticity value near the blackbody locus and a color rendering index greater than 80.

Description

RELATED APPLICATION
This application is a U.S. National Phase Application of PCT International Application No. PCT/US2006/024210, filed Jun. 20, 2006, which claims the benefit of priority to U.S. Provisional Application Ser. No. 60/693,170, filed Jun. 23, 2005 and to U.S. Provisional Application No. 60/698,591, filed Jul. 12, 2005, the contents of each being incorporated by reference herein.
FIELD OF THE INVENTION
The present invention concerns solid-state white light emitting devices. In particular, these devices and methods use a short wavelength light source with both phosphor and quantum dot down conversion materials.
BACKGROUND OF THE INVENTION
Solid state light emitting devices, including solid state lamps having light emitting diodes (LED's) and resonant cavity LED's (RCLED's) are extremely useful, because they potentially offer lower fabrication costs and long term durability benefits over conventional incandescent and fluorescent lamps. Due to their long operation (burn) time and low power consumption, solid state light emitting devices frequently provide a functional cost benefit, even when their initial cost is greater than that of conventional lamps. Because large scale semiconductor manufacturing techniques may be used, many solid state lamps may be produced at extremely low cost.
In addition to applications such as indicator lights on home and consumer appliances, audiovisual equipment, telecommunication devices and automotive instrument markings, LED's have found considerable application in indoor and outdoor informational displays.
With the development of efficient LED's that emit blue or ultraviolet (UV) light, it became feasible to produce LED's that generate white light through phosphor conversion of a portion of the primary emission of the LED to longer wavelengths. Conversion of primary emissions of the LED to longer wavelengths is commonly referred to as down-conversion of the primary emission. An unconverted portion of the primary emission combines with the light of longer wavelength to produce light that may appear white to a viewer. However, using only inorganic phosphors to down-convert short wavelength light, the types of spectra that may be produced efficiently are limited.
SUMMARY OF THE INVENTION
An exemplary embodiment of the present invention is a method of producing visible light using a short wavelength solid state light emitting device, a quantum dot material and a phosphor material, where the visible light has a chromaticity value near the blackbody locus and a color rendering index greater than about 80. Short wavelength light having a first spectrum with a first peak wavelength is generated using the short wavelength solid state light emitting device. The first peak wavelength is shorter than about 500 nm. The quantum dot material is irradiated with at least a portion of the short wavelength light such that a first fraction of the short wavelength light is absorbed and reemitted by the quantum dot material as long wavelength light having a second spectrum with a second peak wavelength. The second peak wavelength is longer than about 600 nm. The phosphor material is irradiated with at least a portion of the short wavelength light such that a second fraction of the short wavelength light is absorbed and reemitted by the phosphor material as mid wavelength light having a third spectrum with a third peak wavelength. The third peak wavelength is between the first peak wavelength and the second peak wavelength. A third fraction of the short wavelength light, at least a portion of the mid wavelength light and at least a portion of the long wavelength light are emitted as the visible light.
Another exemplary embodiment of the present invention is a broad bandwidth light source including: a short wavelength solid state light emitting device; a quantum dot material optically coupled to the short wavelength solid state light emitting device to be irradiated by a first portion of the short wavelength light; and a phosphor material optically coupled to the short wavelength solid state light emitting device to be irradiated by a second portion of the short wavelength light. The short wavelength solid state light emitting device generates short wavelength light having a first spectrum with a first peak wavelength that is shorter than about 500 nm. The quantum dot material is adapted to absorb a fraction of incident light having the first spectrum and reemit it as long wavelength light having a second spectrum with a second peak wavelength that is longer than about 600 nm. The phosphor material is adapted to absorb a fraction of incident light having the first spectrum and reemit it as mid wavelength light having a third spectrum with a peak wavelength that is between the first peak wavelength and the second peak wavelength. The short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that some of the short wavelength light, some of the long wavelength light, and some of the mid wavelength light are emitted substantially coincidentally from the broad bandwidth light source as a visible light having a chromaticity value near the blackbody locus and a color rendering index greater than 80.
A further exemplary embodiment of the present invention is a broad bandwidth light source for producing visible light having a chromaticity value near a blackbody locus and a color rendering index greater than about 80. The broad bandwidth light source includes: means for generating short wavelength light having a first spectrum with a first peak wavelength; means for absorbing and reemitting a first fraction of the short wavelength light as long wavelength light having a second spectrum with a second peak wavelength; and means for absorbing and reemitting a second fraction of the short wavelength light as mid wavelength light having a third spectrum with a third peak wavelength. The first peak wavelength is shorter than about 500 nm, the second peak wavelength is longer than about 600 nm, and the third peak wavelength is between the first peak wavelength and the second peak wavelength. A third fraction of the short wavelength light, at least a portion of the mid wavelength light, and at least a portion of the long wavelength light are emitted as the visible light.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawing are the following figures:
FIG. 1 is a cut away side plan drawing illustrating an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention;
FIG. 2 is a graph illustrating exemplary spectra of a blue light emitting diode, a yellow/green phosphor material, and a red quantum dot (QD) material;
FIG. 3A is a graph illustrating the spectrum of an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention;
FIG. 3B is a CIE-1931 diagram illustrating the color characteristics of an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention;
FIG. 4 is a cut away side plan drawing illustrating another exemplary broad bandwidth light source according to an exemplary embodiment of the present invention;
FIG. 5 is a cut away side plan drawing illustrating a further exemplary broad bandwidth light source according to an exemplary embodiment of the present invention;
FIG. 6 is a flowchart illustrating an exemplary method of producing visible light having a chromaticity value near a blackbody locus and a color rendering index greater than about 80 according to an exemplary embodiment of the present invention;
FIGS. 7A and 7B are schematic block diagrams illustrating exemplary methods of producing visible light using a short wavelength solid state light emitting device, a QD material, and a phosphor material according to an exemplary embodiment of the present invention; and
FIG. 7C is a schematic block diagram illustrating an exemplary method of producing visible light using a short wavelength solid state light emitting device and a combined QD/phosphor material according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Research into solid-state lighting aims not only to develop energy efficient light sources, but also light sources capable of emitting white light that mimics a sunlight spectrum. However, it has been difficult to achieve this type of spectrum efficiently using only inorganic phosphors to down-convert short wavelength light. For example, white LED's using a cerium doped yttrium aluminum garnet (YAG:Ce) phosphor with a gallium nitride (GaN) based blue LED have been produced. In these prior art light sources, a portion of the blue radiation emitted by the GaN LED is down-converted to the green-yellow range by the phosphor. The combined light that results is perceived as white by the human visual system. However, this method has a drawback in that the light produced has a spectrum with a very high correlated color temperature (CCT) and may have poor color rendering properties, especially in the red region. For white LED's to be able to compete with traditional light sources, it is desirable for the spectral power distribution (SPD) to be improved.
Quantum dots (QD's) are nanometer size semiconductors that have the property of absorbing energy in one spectral range and emitting energy in another spectral range. One of the unique features of QD's that may make them interesting in solid-state lighting applications is that the absorption and emission spectra of a QD are related to the average physical size of the QD particle. Therefore, by controlling the diameters of the QD's in a material, theoretically, a material that may produce a tailored, continuous emission spectrum from a narrow bandwidth source may be achieved.
Cadmium selenide-based (CdSe) QD's can be tuned to emit radiation across the entire visible spectrum range (380 nm to 780 nm). Therefore, it is contemplated that CdSe-based QD's are a potential down-conversion material for use in white LED applications. Because the peak wavelength of the emission spectrum of QD's is proportional to their average diameters, it may be possible to combine QD's of different diameters to produce an almost continuous spectrum white light when excited by an ultraviolet or blue LED.
The inventors have tested solid state lighting devices in which red CdSe quantum dots (QD's) (620 nm) have been layered around a blue GaN LED. These tests produced a light source with an output color that is purplish blue and a low luminous efficacy. These results are caused by the lack of output energy by these devices in the green-yellow spectral region.
For general illumination applications, it is almost always desirable to have a light source with a chromaticity near the blackbody locus. The chromaticity of these experimental solid state lighting devices may be improved by adding a certain amount of green QD's to the package. However, it has been found that green QD's have low quantum yields and high self-absorption ratios. Thus, adding green QD's to these experimental light sources may move the chromaticity value of the output light close to the blackbody locus, but the associated quantum yields and self-absorption ratios may greatly decrease package efficiency.
Exemplary embodiments of the present invention include devices and methods to produce white light that may mimic sunlight using light emitting diodes (LED's) and down-conversion materials. These exemplary embodiments use high efficiency red QD's and yellow-green phosphor as down-conversion materials. Hence, the package luminous efficacy may be increased while maintaining the desired chromaticity value.
FIG. 1 illustrates exemplary broad bandwidth light source 100 according to an exemplary embodiment of the present invention. Exemplary broad bandwidth light source 100 includes: short wavelength solid state light emitting device 102 to generate short wavelength light; QD material 104; and phosphor material 106, all of which are mounted on optical mount 108. Optical mount 108 provides mechanical support and may also act as a heat sink to help dissipate heat generated by the short wavelength solid state light emitting device 102 and the down-conversion materials. Optical mount 108 may also have a reflective coating to increase emission of the visible light out of the top surface of exemplary broad bandwidth light source 100. It is noted that, although the positions of QD material 104 and phosphor material 106 shown in FIG. 1 may be desirable, other configurations of these two material layers may be used in exemplary embodiments of the present invention. For example, the positions of QD material 104 and phosphor material 106 may be exchanged in the exemplary embodiment of FIG. 1.
Exemplary broad bandwidth light source 100 addresses the lack of green-yellow light in the spectrum of the experimental solid state light source described above by creating a packaging concept that couples both red QD's and yellow-green phosphor as down-conversion materials with a solid state blue or UV light source. As shown in FIG. 1, short wavelength solid state light emitting device 102 may be embedded within QD material 104 and phosphor material 106 may be layered on top the QD material layer.
FIGS. 7A-C schematically illustrate operation of exemplary broad bandwidth light sources. For simplicity of illustration all photons (arrows) are shown propagating forward. One skilled in the art will understand, however, that down-converted photons may be radiated in all directions and the photons of short wavelength solid state light emitting device 102 may not be collimated as shown in FIGS. 7A-C. In FIGS. 7A-C, short wavelength photons are represented by arrows marked B, mid wavelength photons are represented by arrows marked G and long wavelength photons are represented by arrows marked R. In all three Figures, photons 700 represent the short wavelength photons generated by short wavelength solid state light emitting device 102.
In the exemplary embodiment of FIG. 7A, photons 700 are incident on phosphor material 106 and some of them are absorbed by phosphor material 106 and reemitted as mid wavelength photons. Photons 702 include non-absorbed, short wavelength photons (B) that are transmitted through phosphor material 106 and emitted mid wavelength photons (G). Photons 702 are incident on QD material 104. Some of remaining short wavelength photons and some of the mid wavelength photons are absorbed by QD material 104 and reemitted as long wavelength photons. The remaining short wavelength photons and the remaining mid wavelength photons (G) are transmitted through phosphor material 106 and combine with the emitted long wavelength photons (R) to produce broad bandwidth light 704.
In the exemplary embodiment of FIG. 7B, photons 700 are incident on QD material 104 and some of them are absorbed by QD material 104 and reemitted as long wavelength photons. The remaining short wavelength photons are transmitted through QD material 104. Photons 706 include non-absorbed, short wavelength photons (B) that are transmitted through QD material 104 and emitted long wavelength photons (R). Photons 706 are incident on phosphor material 106. Some of remaining short wavelength photons are absorbed by phosphor material 106 and reemitted as mid wavelength photons. The remaining short wavelength photons (B) and the long wavelength photons (R) are transmitted through phosphor material 106 and combine with the emitted mid wavelength photons (G) to produce broad bandwidth light 704.
In the exemplary embodiment of FIG. 7C, photons 700 are incident on combined QD/phosphor material 402 and some of them are absorbed by combined QD/phosphor material 402 and reemitted as mid wavelength photons and long wavelength photons. The remaining short wavelength photons (B) are transmitted through combined QD/phosphor material 402 and combine with the emitted mid wavelength photons (G) and the long wavelength photons (R) to produce broad bandwidth light 704.
Thus, in all three illustrated embodiments, part of the short wavelength light from short wavelength solid state light emitting device 102 is absorbed by both the QD's in QD material 104 and the phosphor in phosphor material 106 (or in combined QD/phosphor material 402), which absorb the short wavelength light and reemit (i.e. down-convert) it as red and green-yellow light, respectively. Therefore, exemplary broad bandwidth light source 100 may produce an almost continuous spectrum of visible light. As a result, both the chromaticity value and luminous efficacy of exemplary broad bandwidth light source 100 may be improved.
Other benefits of this broad bandwidth light source design may include: increasing the color rendering index (CRI) of the output light; lowering the correlated color temperature (CCT) of the output light; and increasing the efficiency of the device.
FIG. 2 illustrates spectral graph 200, which includes three spectra. Spectrum 202 represents the spectrum of the short wavelength light generated by an exemplary short wavelength solid state light emitting device 102. Spectrum 204 represents the spectrum of the mid wavelength light emitted by an exemplary phosphor material 106. Spectrum 206 represents the spectrum of the long wavelength light emitted by an exemplary QD material 104. By properly configuring short wavelength solid state light emitting device 102, QD material 104, and phosphor material 106, the relative amounts of light from each of these spectra may be controlled to produce a visible light with desired optical properties such as chromaticity, CRI, and CCT. Spectral graph 300 in FIG. 3A illustrates exemplary combined spectrum 302 that may be produced in this manner.
By varying the relative contributions of spectrum 202, spectrum 204, and spectrum 206 to the visible light emitted by exemplary broad bandwidth light source 100, the chromaticity value of the emitted light may be changed. The chromaticity value of the emitted light may also be changed by choosing a short wavelength solid state light emitting device, a QD material, and/or a phosphor material that have different spectra than those shown in FIG. 2. As noted above, a chromaticity near the black body locus has been found to be most natural to people and, thus, preferred for lighting designs. FIG. 3B shows CIE-1931 diagram 304 on which spectrum locus 306, black body locus 308, and chromaticity value 310 of exemplary combined spectrum 302 shown in FIG. 3A have been plotted. As may be seen in FIG. 3B, chromaticity value 310 of exemplary combined spectrum 302 shown in FIG. 3A is very near to black body locus 308. Proper selection and configuration of short wavelength solid state light emitting device 102, QD material 104, and phosphor material 106 may allow the chromaticity value of the visible light emitted from broad bandwidth light source 100 to be desirably set within an area bounded by about 0.01 of the x chromaticity value and about 0.01 of the y chromaticity value of the blackbody locus on a CIE-1931 diagram.
CRI is a figure of merit, on a scale of 0 to 100, used by manufacturers of fluorescent, metal halide and other nonincandescent lighting equipment to describe the visual effect of the light on colored surfaces. Natural daylight and any light source approximating a blackbody source (see color temperature) are assigned a CRI of 100. In a daylighting context, the CRI defines the spectral transmissive quality of glasses or other transparent materials. In this case, values of 95 or better are considered acceptable for allowing true color rendering. Typical cool white fluorescent lamps have a CRI of approximately 62. Fluorescent lamps having rare-earth phosphors have achieved CRI's of 80 and above. The CRI of a typical white LED based on a blue LED and YAG phosphor is between 70 and 78. Proper selection and configuration of short wavelength solid state light emitting device 102, QD material 104, and phosphor material 106 may allow the CRI of the visible light emitted from broad bandwidth light source 100 to be desirably set to be greater than about 85 or even greater than about 90.
Short wavelength solid state light emitting device 102 generates short wavelength light that desirably has a peak wavelength shorter than about 500 nm, for example between about 200 nm and about 500 nm.
The solid state light emitting device may be a light emitting diode (LED), a resonant cavity LED, or a diode laser. Examples of materials from which these devices may be formed include: InGaN; GaN; SiC; GaN on a SiC, and other semiconductor materials.
QD material 104 is optically coupled to short wavelength solid state light emitting device 102 so that it may be irradiated by a portion of the short wavelength light. In FIG. 1, QD material 104 is shown to surround short wavelength solid state light emitting device 102. One skilled in the art will understand that this is not necessary, however, as long as QD material 104 is sufficiently irradiated with the short wavelength light. Providing space between QD material 104 and short wavelength solid state light emitting device 102 may be desirable to reduce optical coupling of short wavelength light emitted by QD material 104 into short wavelength solid state light emitting device 102. Such ‘back coupling’ of longer wavelength light may lead to undesirable heating of short wavelength solid state light emitting device 102.
QD material 104 is adapted to absorb a fraction of incident short wavelength light and to reemit the absorbed light as long wavelength light having a peak wavelength that is longer than about 600 nm, for example between about 600 nm and about 700 nm. The full width half maximum (FWHW) of the spectrum of the long wavelength light emitted by QD material 104 may be less than about 50 nm, although in some applications a broader spectrum of long wavelength light may be desirable. A broader spectrum of long wavelength light may be particularly desirable if a component of infrared light is to be added to the visible. It is noted that a small contribution of infrared light to visible light has been found to have beneficial psychological and physical effects for some people.
QD material 104 includes a large number of QD's that are dispersed within a matrix material. This matrix material is desirably substantially transmissive to the visible light being produced by broad bandwidth light source 100. For example, the matrix material may include: UV curable clear resin; thermal curable sol-gel resin; UV curable sol-gel resin; polycarbonate; polystyrene; polymethyl methacrylate (PMMA); polyethylene; various epoxies; silicones; silica; or titania.
The QD's typically have a diameter in range of about 1.9 nm to about 10.0 nm, although this range is not limiting, and may be formed of any standard QD material, such as CdSe, ZnS, PbSe, CdTe, PbTe, ZnSe, Si, or Ge, among others.
Phosphor material 106 is adapted to absorb a fraction of incident short wavelength light and to reemit the absorbed light as a mid wavelength light having a peak wavelength between the peak wavelength of the short wavelength light and the peak wavelength of the long wavelength light, often desirably between about 500 nm and about 600 nm. The full width half maximum of the spectrum of the mid wavelength light emitted by phosphor material 106 may be less than about 150 nm, depending on the specific phosphor used.
Phosphor material 106 may includes a large number of phosphor particles that are dispersed within a matrix material. As with the matrix material of QD material 104, this matrix material is desirably substantially transmissive to the visible light being produced by broad bandwidth light source 100 and may include, for example: UV curable clear resin; thermal curable sol-gel resin; UV curable sol-gel resin; polycarbonate; polystyrene; polymethyl methacrylate (PMMA); polyethylene; various epoxies; silicones; silica; or titania. Alternatively, phosphor material 106 may be a bulk phosphor material, possibly formed into a flat substrate as shown in FIG. 1.
The phosphor particles or the bulk phosphor material may include at least one standard yellow or green phosphor, such as: ZnS:Cu—Al; ZnSiO4:Mn2+; Sr3SiO5:Eu2+; BaMgAl10O17:Eu2+Mn2+; SrAlO4:Eu,Dy; (YGdCe)3Al5O12:Eu; Sr4Al14O25:Eu; (Ce, Tb)MgAl11O19; or (La, Ce, Tb)PO4, YAG:Ce, or other phosphors.
Exemplary broad bandwidth light source 100 illustrated in FIG. 1 is configured such that the short wavelength light with which phosphor material 106 is irradiated has first been transmitted through QD material 104 before it is incident on the phosphor material. Although it is contemplated that the positions of QD material 104 and phosphor material 106 may be reversed, the configuration shown in FIG. 1 may provide an advantage. As noted above, ‘back coupling’ of light into short wavelength solid state light emitting device 102 may lead to undesirable heating. If QD material 104 is adapted to absorb and reemit a fraction of the incident mid wavelength light as well as a fraction of the short wavelength light, the configuration shown in FIG. 1 may desirably reduce the amount of mid wavelength light that is back coupled into short wavelength solid state light emitting device 102.
FIGS. 4 and 5 illustrate alternative exemplary broad bandwidth light sources 400 and 500, respectively. Each of these alternative exemplary broad bandwidth light sources includes a combined QD/phosphor material. This combined QD/phosphor material includes a plurality of QD's and a plurality of phosphor particles that are dispersed within a matrix material that is substantially transmissive to the visible light of the exemplary broad bandwidth light source. The QD's and the phosphor particles may be dispersed separately in specific regions of the matrix material, or they may be mixedly dispersed within the matrix material.
FIG. 4 illustrates exemplary broad bandwidth light source 400 in which combined QD/phosphor material 402 is formed surrounding short wavelength solid state light emitting device 102. FIG. 5 illustrates exemplary broad bandwidth light source 500 in which combined QD/phosphor material 502 is formed on the surface of optical element 504. Optical element 504 may desirably be a light guide that may help to reduce back coupling of mid and long wavelength light from combined QD/phosphor material 502 into short wavelength solid state light emitting device 102.
An exemplary broad bandwidth light source according to the exemplary embodiment of FIG. 1 was formed using a GaN-based bare blue LED device as short wavelength solid state light emitting device 102. This blue LED was immersed in a layer of red QD's that had a peak emission wavelength of 630 nm (QD material 104) and a YAG yellow/green phosphor layer (phosphor material 106) was placed in front of the LED and QD material. Measurements of this exemplary device show that the package luminous efficacy was 211 m/W, which is close to that of a corresponding commercially available white LED device which uses a phosphor only down conversion material (231 m/W). However, the exemplary broad bandwidth light source, which produced the exemplary data shown in FIGS. 3A and 3B, had a CRI of 90 with a chromaticity value close to the blackbody locus. Thus, the inventors were able to demonstrate an exemplary broad bandwidth light source according to an exemplary embodiment of the present invention that achieves superior color quality with a minimal reduction of luminous efficacy.
FIG. 6 illustrates an exemplary method of producing visible light using a short wavelength solid state light emitting device, a QD material, and a phosphor material. The visible light produced by this exemplary method has a chromaticity value near the blackbody locus and a CRI greater than about 80. This method may desirably use any of the exemplary broad bandwidth light sources described above with reference to FIG. 1, 4, or 5.
Short wavelength light is generated using the short wavelength solid state light emitting device, step 600. The short wavelength light has a first spectrum with a peak wavelength that is desirably shorter than about 500 nm.
The QD material is irradiated with at least a portion of the short wavelength light such that a fraction of the short wavelength light is absorbed and reemitted by the QD material as long wavelength light, step 604. The long wavelength light has a second spectrum with a peak wavelength which is desirably longer than about 600 nm.
The phosphor material is also irradiated with at least a portion of the short wavelength light such that a fraction of the short wavelength light is absorbed and reemitted by the phosphor material as mid wavelength light, step 602. The mid wavelength light has a third spectrum with a peak wavelength between the peak wavelengths of the short wavelength light and the long wavelength light.
A remainder of the short wavelength light, at least a portion of the mid wavelength light, and at least a portion of the long wavelength light are emitted from the as exemplary broad bandwidth light source the visible light, step 606.
Alternatively, the QD material may be irradiated with at least a portion of the mid wavelength light in addition to the short wavelength light. A fraction of the mid wavelength light may be absorbed and reemitted by the QD material as additional long wavelength light, step 608.
Although the invention is illustrated and described herein with reference to specific embodiments, it is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention. In particular, one skilled in the art may understand that many features of the various specifically illustrated embodiments may be mixed to form additional exemplary broad bandwidth light sources and methods also embodied by the present invention.

Claims (38)

1. A method of producing visible light having a chromaticity value near a blackbody locus and a color rendering index greater than about 80, the visible light produced using a short wavelength solid state light emitting device, a quantum dot material and a phosphor material spaced apart from the quantum dot material, the method comprising:
a) generating short wavelength light having a first spectrum with a first peak wavelength using the short wavelength solid state light emitting device, the first peak wavelength being shorter than about 500 nm;
b) irradiating the quantum dot material or the spaced apart phosphor material with at least a portion of the short wavelength light such that a first fraction of the short wavelength light is absorbed and reemitted by the quantum dot material or the spaced apart phosphor material as longer wavelength light having a second spectrum with a second peak wavelength, the second peak wavelength being longer than the first peak wavelength;
c) irradiating another of the quantum dot material or the spaced apart phosphor material with at least another portion of the short wavelength light such that a second fraction of the short wavelength light is absorbed and reemitted by the other of the quantum dot material or the spaced apart phosphor material as light having a third spectrum with a third peak wavelength, the third peak wavelength being either between the first peak wavelength and the second peak wavelength or longer than the second peak wavelength; and
d) emitting a third fraction of the short wavelength light and combining the third fraction of the short wavelength light with at least a portion of the second wavelength light, and at least a portion of the third wavelength light as the visible light.
2. A method according to claim 1, wherein the chromaticity value of the visible light emitted in step (d) is within an area bounded by about 0.01 of an x chromaticity value and about 0.01 of a y chromaticity value of the blackbody locus on a CIE-1931 diagram.
3. A method according to claim 1, wherein the color rendering index of the visible light emitted in step (d) is greater than about 85.
4. A method according to claim 1, wherein the color rendering index of the visible light emitted in step (d) is greater than about 90.
5. A method according to claim 1, wherein the visible light emitted in step (d) has a correlated color temperature less between about 1000K and about 16000K.
6. A method according to claim 1, wherein the visible light emitted in step (d) has a correlated color temperature between about 3300K and about 3600K.
7. A method according to claim 1, wherein the first peak wavelength of the short wavelength light generated in step (a) by the short wavelength solid state light emitting device is between about 200 nm and about 500 nm.
8. A method according to claim 1, wherein the second peak wavelength of the long wavelength light emitted in step (b) by the quantum dot material is between about 600 nm and about 700 nm.
9. A method according to claim 1, wherein a full width half maximum of the second spectrum of the long wavelength light generated in step (b) by the quantum dot material is less than about 50 nm.
10. A method according to claim 1, wherein step (b) further includes irradiating the quantum dot material with at least a portion of the mid wavelength light such that a fourth fraction of the mid wavelength light is absorbed and reemitted by the quantum dot material as additional long wavelength light.
11. A method according to claim 1, wherein the third peak wavelength of the mid wavelength light emitted in step (c) by the phosphor material is between about 500 nm and about 600 nm.
12. A method according to claim 1, wherein a full width half maximum of the third spectrum of the mid wavelength light generated in step (c) by the phosphor material is less than about 150 nm.
13. A broad bandwidth light source comprising:
a short wavelength solid state light emitting device to generate short wavelength light having a first spectrum with a first peak wavelength, the first peak wavelength being shorter than about 500 nm;
a quantum dot material and a phosphor material optically coupled to the short wavelength solid state light emitting device, the quantum dot material or the phosphor material to be irradiated by a first portion of the short wavelength light, the quantum dot material or the phosphor material adapted to absorb a first fraction of incident light having the first spectrum and to reemit the absorbed light as longer wavelength light having a second spectrum with a second peak wavelength, the second peak wavelength being longer than the first peak wavelength peak; and
another of the quantum dot material or the phosphor material to be irradiated by a second portion of the short wavelength light, the other of the quantum dot material or the phosphor material adapted to absorb a second fraction of incident light having the first spectrum and to reemit the absorbed light as light having a third spectrum with a third peak wavelength, the third peak wavelength either being between the first peak wavelength and the second peak wavelength or longer than the second peak wavelength,
wherein the short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that a first amount of the short wavelength light, a second amount of the longer wavelength light, and a third amount of the third wavelength light are emitted substantially coincidentally from the broad bandwidth light source as a visible light having a chromaticity value near a blackbody locus and a color rendering index greater than 80;
and further comprising an optical element optically coupled to the quantum dot material and the phosphor material for controlling back coupling of light from the quantum dot material and the phosphor material into the short wavelength solid state light emitting device.
14. A broad bandwidth light source according to claim 13, wherein the short wavelength solid state light emitting device is one of a short wavelength light emitting diode (LED), a short wavelength resonant cavity LED, or a short wavelength diode laser.
15. A broad bandwidth light source according to claim 13, wherein the first peak wavelength of the short wavelength light generated by the short wavelength solid state light emitting device is between about 200 nm and about 500 nm.
16. A broad bandwidth light source according to claim 13, wherein a full width half maximum of the first spectrum of the short wavelength light generated by the short wavelength solid state light emitting device is less than about 50 nm.
17. A broad bandwidth light source according to claim 13, wherein the quantum dot material includes a plurality of quantum dots dispersed within a matrix material that is substantially transmissive to the visible light.
18. A broad bandwidth light source according to claim 17, wherein the plurality of quantum dots include at least one of CdSe quantum dots, ZnS quantum dots, CdTe quantum dots, PbTe quantum dots, ZnSe quantum dots, Si quantum dots, Ge quantum dots, or PbSe quantum dots.
19. A broad bandwidth light source according to claim 17, wherein the matrix material includes at least one of UV curable clear resin, thermal curable sol-gel resin, UV curable sol-gel resin, polycarbonate, polystyrene, polymethyl methacrylate (PMMA), polyethylene, epoxies, silicones, silica, or titania.
20. A broad bandwidth light source according to claim 13, wherein the second peak wavelength of the long wavelength light emitted by the quantum dot material is between about 600 nm and about 700 nm.
21. A broad bandwidth light source according to claim 13, wherein a full width half maximum of the second spectrum of the long wavelength light generated by the quantum dot material is less than about 50 nm.
22. A broad bandwidth light source according to claim 13, wherein:
the quantum dot material or the phosphor material is further optically coupled to the other of the quantum dot material or the phosphor material to be irradiated by a portion of the longer wavelength light; and
the other of the quantum dot material or the phosphor material is further adapted to absorb a third fraction of incident light having the first spectrum.
23. A broad bandwidth light source according to claim 22, wherein the quantum dot material is disposed within the broad bandwidth light source such that the second portion of the short wavelength light with which the phosphor material is irradiated is transmitted through the quantum dot material before being incident on the phosphor material.
24. A broad bandwidth light source according to claim 13, wherein the phosphor material includes a plurality of phosphor particles dispersed within a matrix material that is substantially transmissive to the visible light.
25. A broad bandwidth light source according to claim 24, wherein the plurality of phosphor particles include at least one of ZnS:Cu—Al; ZnSiO4:Mn2+; Sr3SiO5:Eu2+; BaMgAl10O17:Eu2+Mn2+; SrAlO4:Eu,Dy; (YGdCe)3Al5O12:Eu; YAG:Ce; Sr4Al14O25:Eu; (Ce, Tb)MgAl11O19; YAG:Ce; or (La, Ce, Tb)PO4.
26. A broad bandwidth light source according to claim 24, wherein the matrix material includes at least one of UV curable clear resin, thermal curable sol-gel resin, UV curable sol-gel resin, polycarbonate, polystyrene, polymethyl methacrylate (PMMA), polyethylene, epoxies, silicones, silica, or titania.
27. A broad bandwidth light source according to claim 13, wherein the phosphor material includes at least one of bulk ZnS:Cu—Al; bulk ZnSiO4:Mn2+; bulk Sr3SiO5:Eu2+; bulk BaMgAl10O17:Eu2+Mn2+; bulk SrAlO4:Eu,Dy; bulk (YGdCe)3Al5O12:Eu; bulk Sr4Al14O25:Eu; bulk (Ce, Tb)MgAl11O19; or bulk (La, Ce, Tb)PO4.
28. A broad bandwidth light source according to claim 13, wherein the third peak wavelength of the longer wavelength light emitted by the phosphor material is between either about 500 nm and about 600 nm or about 600 nm and 700 nm.
29. A broad bandwidth light source according to claim 13, wherein a full width half maximum of the third spectrum of the longer wavelength light generated by the phosphor material is less than about 150 nm.
30. A broad bandwidth light source according to claim 13, wherein the short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that the chromaticity value of the visible light emitted from the broad bandwidth light source is within an area bounded by about 0.01 of an x chromaticity value and about 0.01 of a y chromaticity value of the blackbody locus on a CIE-1931 diagram.
31. A broad bandwidth light source according to claim 13, wherein the short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that the color rendering index of the visible light emitted from the broad bandwidth light source is greater than about 85.
32. A broad bandwidth light source according to claim 2, wherein the short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that the color rendering index of the visible light emitted from the broad bandwidth light source is greater than about 90.
33. A broad bandwidth light source according to claim 13, wherein the short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that the color rendering index of the visible light emitted from the broad bandwidth light source has a correlated color temperature between about 1000K and about 16000K.
34. A broad bandwidth light source according to claim 13, wherein the short wavelength solid state light emitting device, the quantum dot material, and the phosphor material are configured such that the color rendering index of the visible light emitted from the broad bandwidth light source has a correlated color temperature between about 3300K and about 3600K.
35. A broad bandwidth light source for producing visible light having a chromaticity value near a blackbody locus and a color rendering index greater than about 80, the broad bandwidth light source comprising:
means for generating short wavelength light having a first spectrum with a first peak wavelength, the first peak wavelength being shorter than about 500 nm;
means for absorbing and reemitting a first fraction of the short wavelength light as longer wavelength light having a second spectrum with a second peak wavelength, the second peak wavelength being longer than the first peak wavelength; and
means for absorbing and reemitting a second fraction of the short wavelength light as light having a third spectrum with a third peak wavelength, the third peak wavelength being either between the first peak wavelength and the second peak wavelength or longer than the second peak wavelength,
wherein a third fraction of the short wavelength light, at least a portion of the longer wavelength light, and at least a portion of the light having the third spectrum are emitted as the visible light;
and further comprising an optical element optically coupled
to the means for absorbing and reemitting a first fraction of the short wavelength light and
to the means for absorbing and reemitting a second fraction of the short wavelength light
 for controlling back coupling of light from
the means for absorbing and reemitting a first fraction of the short wavelength light and
the means for absorbing and reemitting a second fraction of the short wavelength light
 into the means for generating short wavelength light.
36. The broad bandwidth light source of claim 13, wherein the phosphor material is separate from the quantum dot material.
37. The broad bandwidth light source of claim 13, wherein the phosphor material is spaced apart from the quantum dot material.
38. A broad bandwidth light source comprising:
a short wavelength solid state light emitting device to generate short wavelength light having a first spectrum with a first peak wavelength, the first peak wavelength being shorter than about 500 nm;
a quantum dot material having a plurality of quantum dots and a phosphor material having a plurality of phosphor particles, the plurality of quantum dots and the plurality of phosphor particles being
optically coupled to the short wavelength solid state light emitting device to be irradiated by a first portion of the short wavelength light and
mixedly dispersed within a matrix material that is substantially transmissive to visible light, the mixedly dispersed plurality of quantum dots and plurality of phosphor materials adapted to
absorb a first fraction of incident light having the first spectrum and reemit the absorbed light as mid wavelength light and long wavelength light,
wherein the mid wavelength light and the long wavelength light combine with a second fraction of incident light that is transmitted through the mixedly dispersed plurality of quantum dots and plurality of phosphor particles to produce broad bandwidth light as a visible light as visible light; and
an optical element optically coupled to the mixedly dispersed plurality of quantum dots and plurality of phosphor particles for controlling back coupling of light from the mixedly dispersed plurality of quantum dots and plurality of phosphor particles into the short wavelength solid state light emitting device.
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Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090268461A1 (en) * 2008-04-28 2009-10-29 Deak David G Photon energy conversion structure
US20100109568A1 (en) * 2004-11-12 2010-05-06 Koninklijke Philips Electronics N.V. Common optical element for an array of phosphor converted llight emitting devices
US20100144231A1 (en) * 2008-12-04 2010-06-10 Daniel Landry Method of matching color in lighting applications
US20110103064A1 (en) * 2008-05-06 2011-05-05 Seth Coe-Sullivan Solid state lighting devices including quantum confined semiconductor nanoparticles, an optical component for a solid state lighting device, and methods
US20110164430A1 (en) * 2010-01-07 2011-07-07 Kenneth Li Illuminator using light emitting diode light recycling with collimation
US20120217865A1 (en) * 2011-02-25 2012-08-30 Cree, Inc. Solid state light emitting devices including nonhomogeneous luminophoric particle size layers
US20130016499A1 (en) * 2010-12-28 2013-01-17 Young Joo Yee Optical device and light emitting diode package using the same, and backlight apparatus
US20130039617A1 (en) * 2010-04-27 2013-02-14 Stefan Illek Optoelectronic Component and Method for Producing an Optoelectronic Component
US20130043786A1 (en) * 2011-08-19 2013-02-21 Epistar Corporation Wavelength conversion structure, manufacturing method thereof, and light-emitting device comprising the wavelength conversion structure
US20130163866A1 (en) * 2011-12-23 2013-06-27 Research In Motion Limited Apparatus, and associated method, for facilitating white balancing of an image
US20130241392A1 (en) * 2006-01-20 2013-09-19 Cree, Inc. Lighting devices having remote lumiphors that are excited by lumiphor-converted semiconductor excitation sources
US20140009929A1 (en) * 2012-02-02 2014-01-09 Flextronics Automotive Gmbh & Co Kg Lamp with a translucent plastic element
US20140022779A1 (en) * 2011-04-01 2014-01-23 Kai Su White light emitting device
US8957438B2 (en) 2011-04-07 2015-02-17 Cree, Inc. Methods of fabricating light emitting devices including multiple sequenced luminophoric layers
US8981339B2 (en) 2009-08-14 2015-03-17 Qd Vision, Inc. Lighting devices, an optical component for a lighting device, and methods
US20150083933A1 (en) * 2013-09-25 2015-03-26 Phoseon Technology, Inc. Multi-wavelength led curing lamp
US9101036B2 (en) 2010-08-20 2015-08-04 Research Triangle Institute Photoluminescent nanofiber composites, methods for fabrication, and related lighting devices
US9133388B2 (en) 2009-04-28 2015-09-15 Qd Vision, Inc. Optical materials, optical components, and methods
US9134459B2 (en) 2009-10-17 2015-09-15 Qd Vision, Inc. Optical component, products including same, and methods for making same
US9140844B2 (en) 2008-05-06 2015-09-22 Qd Vision, Inc. Optical components, systems including an optical component, and devices
US9207385B2 (en) 2008-05-06 2015-12-08 Qd Vision, Inc. Lighting systems and devices including same
US20150362643A1 (en) * 2014-06-11 2015-12-17 Hitachi Maxell, Ltd. Diffractive lens and optical device using the same
US9423551B2 (en) 2014-03-10 2016-08-23 Samsung Display Co., Ltd. Backlight assembly and display apparatus having the same
US9441811B2 (en) 2010-08-20 2016-09-13 Research Triangle Institute Lighting devices utilizing optical waveguides and remote light converters, and related methods
US20170005239A1 (en) * 2015-06-30 2017-01-05 Nichia Corporation Light emitting device
US9562671B2 (en) 2010-08-20 2017-02-07 Research Triangle Institute Color-tunable lighting devices and methods of use
US9905735B1 (en) * 2017-03-31 2018-02-27 Cree, Inc. High brightness, low-cri semiconductor light emitting devices including narrow-spectrum luminescent materials
US10158057B2 (en) 2010-10-28 2018-12-18 Corning Incorporated LED lighting devices
US10818827B2 (en) 2017-09-28 2020-10-27 Nichia Corporation Light-emitting device
US11043618B2 (en) 2015-11-02 2021-06-22 Nanoco Technologies Ltd. Display devices comprising green-emitting quantum dots and red KSF phosphor

Families Citing this family (81)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007103310A2 (en) 2006-03-07 2007-09-13 Qd Vision, Inc. An article including semiconductor nanocrystals
US8718437B2 (en) 2006-03-07 2014-05-06 Qd Vision, Inc. Compositions, optical component, system including an optical component, devices, and other products
CN101138104B (en) * 2005-06-23 2011-08-24 伦斯勒工业学院 Package design for producing white light with short-wavelength leds and down-conversion materials
TWI396814B (en) 2005-12-22 2013-05-21 克里公司 Lighting device
US8264138B2 (en) * 2006-01-20 2012-09-11 Cree, Inc. Shifting spectral content in solid state light emitters by spatially separating lumiphor films
US9874674B2 (en) 2006-03-07 2018-01-23 Samsung Electronics Co., Ltd. Compositions, optical component, system including an optical component, devices, and other products
US9951438B2 (en) 2006-03-07 2018-04-24 Samsung Electronics Co., Ltd. Compositions, optical component, system including an optical component, devices, and other products
KR100764391B1 (en) * 2006-04-25 2007-10-05 삼성전기주식회사 Light emitting diode module
BRPI0718085A2 (en) * 2006-10-31 2013-11-05 Tir Technology Lp LIGHT SOURCE
US8836212B2 (en) 2007-01-11 2014-09-16 Qd Vision, Inc. Light emissive printed article printed with quantum dot ink
US20080198572A1 (en) 2007-02-21 2008-08-21 Medendorp Nicholas W LED lighting systems including luminescent layers on remote reflectors
WO2009014590A2 (en) 2007-06-25 2009-01-29 Qd Vision, Inc. Compositions and methods including depositing nanomaterial
WO2009014707A2 (en) 2007-07-23 2009-01-29 Qd Vision, Inc. Quantum dot light enhancement substrate and lighting device including same
US8128249B2 (en) 2007-08-28 2012-03-06 Qd Vision, Inc. Apparatus for selectively backlighting a material
JP5044329B2 (en) * 2007-08-31 2012-10-10 株式会社東芝 Light emitting device
TWI397193B (en) * 2007-11-05 2013-05-21 Univ Nat Chunghsing Light emitting diode chip element with heat dissipation substrate and method for making the same
WO2009107535A1 (en) * 2008-02-25 2009-09-03 株式会社東芝 White led lamp, backlight, light emitting device, display device and lighting device
KR20110009702A (en) * 2008-05-13 2011-01-28 리써치 트라이앵글 인스티튜트 Porous and non-porous nanostructures and application thereof
KR100982991B1 (en) * 2008-09-03 2010-09-17 삼성엘이디 주식회사 Quantum dot-wavelength conversion device, preparing method of the same and light-emitting device comprising the same
DE102008050643B4 (en) 2008-10-07 2022-11-03 OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung bulbs
US20100135009A1 (en) * 2008-10-15 2010-06-03 David Duncan Custom color led replacements for traditional lighting fixtures
US8220971B2 (en) 2008-11-21 2012-07-17 Xicato, Inc. Light emitting diode module with three part color matching
US8360617B2 (en) * 2008-11-25 2013-01-29 Samsung Electronics Co., Ltd. Lighting system including LED with glass-coated quantum-dots
US8169135B2 (en) * 2008-12-17 2012-05-01 Lednovation, Inc. Semiconductor lighting device with wavelength conversion on back-transferred light path
KR101493708B1 (en) * 2008-12-26 2015-02-16 삼성전자주식회사 White light emitting device
US7923741B1 (en) 2009-01-05 2011-04-12 Lednovation, Inc. Semiconductor lighting device with reflective remote wavelength conversion
RU2526809C2 (en) * 2009-04-06 2014-08-27 Конинклейке Филипс Электроникс Н.В. Luminescent converter for phosphor-enhanced light source comprising organic and inorganic phosphors
US8337030B2 (en) 2009-05-13 2012-12-25 Cree, Inc. Solid state lighting devices having remote luminescent material-containing element, and lighting methods
US8217567B2 (en) 2009-06-11 2012-07-10 Cree, Inc. Hot light emitting diode (LED) lighting systems
US8901845B2 (en) 2009-09-24 2014-12-02 Cree, Inc. Temperature responsive control for lighting apparatus including light emitting devices providing different chromaticities and related methods
US9713211B2 (en) 2009-09-24 2017-07-18 Cree, Inc. Solid state lighting apparatus with controllable bypass circuits and methods of operation thereof
US10264637B2 (en) 2009-09-24 2019-04-16 Cree, Inc. Solid state lighting apparatus with compensation bypass circuits and methods of operation thereof
EP2480816A1 (en) 2009-09-25 2012-08-01 Cree, Inc. Lighting device with low glare and high light level uniformity
US8777449B2 (en) * 2009-09-25 2014-07-15 Cree, Inc. Lighting devices comprising solid state light emitters
US9068719B2 (en) * 2009-09-25 2015-06-30 Cree, Inc. Light engines for lighting devices
US8602579B2 (en) 2009-09-25 2013-12-10 Cree, Inc. Lighting devices including thermally conductive housings and related structures
US9285103B2 (en) * 2009-09-25 2016-03-15 Cree, Inc. Light engines for lighting devices
US8466611B2 (en) 2009-12-14 2013-06-18 Cree, Inc. Lighting device with shaped remote phosphor
US9631782B2 (en) 2010-02-04 2017-04-25 Xicato, Inc. LED-based rectangular illumination device
US8104908B2 (en) * 2010-03-04 2012-01-31 Xicato, Inc. Efficient LED-based illumination module with high color rendering index
US8476836B2 (en) 2010-05-07 2013-07-02 Cree, Inc. AC driven solid state lighting apparatus with LED string including switched segments
US9689556B2 (en) 2010-05-27 2017-06-27 Merck Patent Gmbh Down conversion array comprising quantum dots
CN102376860A (en) 2010-08-05 2012-03-14 夏普株式会社 Light emitting apparatus and method for manufacturing thereof
JP2012036265A (en) * 2010-08-05 2012-02-23 Sharp Corp Illuminating device
US20120051045A1 (en) 2010-08-27 2012-03-01 Xicato, Inc. Led Based Illumination Module Color Matched To An Arbitrary Light Source
US9648673B2 (en) 2010-11-05 2017-05-09 Cree, Inc. Lighting device with spatially segregated primary and secondary emitters
WO2012088404A1 (en) 2010-12-23 2012-06-28 Qd Vision, Inc. Quantum dot containing optical element
US20120154917A1 (en) * 2011-01-18 2012-06-21 Eric William Hearn Teather Color-shifting reflector
CN103460809B (en) * 2011-03-31 2015-04-22 柯尼卡美能达美国研究所有限公司 Adaptive lighting system with low energy consumption
JP5105132B1 (en) 2011-06-02 2012-12-19 三菱化学株式会社 Semiconductor light emitting device, semiconductor light emitting system, and lighting fixture
US9839083B2 (en) 2011-06-03 2017-12-05 Cree, Inc. Solid state lighting apparatus and circuits including LED segments configured for targeted spectral power distribution and methods of operating the same
US8742671B2 (en) 2011-07-28 2014-06-03 Cree, Inc. Solid state lighting apparatus and methods using integrated driver circuitry
KR101859653B1 (en) * 2011-08-30 2018-05-18 삼성전자주식회사 Light emitting unit and liquid display apparatus having the same
US20130062639A1 (en) * 2011-09-12 2013-03-14 SemiLEDs Optoelectronics Co., Ltd. Method for fabricating light emitting diode (led) devices having output with selected characteristics
EP2791574B1 (en) * 2011-12-16 2016-05-18 Koninklijke Philips N.V. Optical arrangement with diffractive optics
JP2013201274A (en) * 2012-03-23 2013-10-03 Toshiba Lighting & Technology Corp Luminaire
JP6382792B2 (en) * 2012-03-30 2018-08-29 コーニンクレッカ フィリップス エヌ ヴェKoninklijke Philips N.V. Optical cavity including light emitting device and wavelength converting material
WO2013150455A1 (en) 2012-04-05 2013-10-10 Koninklijke Philips N.V. Full spectrum light emitting arrangement
KR101907390B1 (en) * 2012-04-23 2018-10-12 삼성전자주식회사 White light emitting device and display apparatus
US9929325B2 (en) 2012-06-05 2018-03-27 Samsung Electronics Co., Ltd. Lighting device including quantum dots
CN104521016B (en) * 2012-08-10 2018-07-10 亮锐控股有限公司 Phosphor converted LEDs, lamp and luminaire
KR20150132354A (en) * 2013-03-14 2015-11-25 코닝 인코포레이티드 Led lighting devices
KR20150092801A (en) 2014-02-05 2015-08-17 삼성디스플레이 주식회사 Light Emitting Diode Package and Method of manufacturing the same
KR20150115082A (en) * 2014-04-02 2015-10-14 삼성디스플레이 주식회사 Backlight unit and display divece having the same
DE102014107972B9 (en) * 2014-04-17 2022-07-21 OSRAM Opto Semiconductors Gesellschaft mit beschränkter Haftung Lighting device with a first phosphor and filter particles
US9660151B2 (en) * 2014-05-21 2017-05-23 Nichia Corporation Method for manufacturing light emitting device
JP6428089B2 (en) 2014-09-24 2018-11-28 日亜化学工業株式会社 Light emitting device
US10490711B2 (en) * 2014-10-07 2019-11-26 Nichia Corporation Light emitting device
KR101629331B1 (en) * 2014-12-11 2016-06-10 엘지전자 주식회사 Display device and Cooking appliance having it
DE102015105486A1 (en) * 2015-04-10 2016-10-13 Osram Opto Semiconductors Gmbh Optoelectronic component and method for its production
JP6100831B2 (en) * 2015-05-26 2017-03-22 シャープ株式会社 Light emitting device and image display device
CN105610514A (en) * 2015-12-31 2016-05-25 固安翌光科技有限公司 Visible light communication system of white-light OLED (Organic Light Emitting Diode) device based on quantum dots
CN105549262A (en) * 2016-02-03 2016-05-04 青岛海信电器股份有限公司 Backlight unit, backlight source module and liquid-crystal display device
CN105990504A (en) * 2016-07-06 2016-10-05 华南师范大学 White LED with quantum dots cured and packaged by UV adhesive as fluorescence conversion material, and preparation method and applications thereof
CN107123727B (en) * 2017-05-15 2018-03-27 华中科技大学 A kind of quantum spot white light LED of low operating temperature and preparation method thereof
CN106972092B (en) * 2017-05-15 2018-07-03 华中科技大学 A kind of quantum spot white light LED of high-luminous-efficiency and preparation method thereof
WO2018232192A1 (en) * 2017-06-14 2018-12-20 Ubiqd Inc. Fiber-coupled broadband light source
CN109708026B (en) * 2017-10-25 2021-12-31 苏州星烁纳米科技有限公司 Lighting lamp
EP3729520A1 (en) * 2017-12-18 2020-10-28 LITEC-Vermögensverwaltungsgesellschaft mbH Light-converting material
WO2020043709A1 (en) * 2018-08-29 2020-03-05 Osa Opto Light Gmbh Wide-band emitter for electromagnetic radiation
TW202017209A (en) * 2018-10-22 2020-05-01 隆達電子股份有限公司 Light emitting diode package with enhanced quantum dot reliability

Citations (137)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3593055A (en) 1969-04-16 1971-07-13 Bell Telephone Labor Inc Electro-luminescent device
US3760237A (en) 1972-06-21 1973-09-18 Gen Electric Solid state lamp assembly having conical light director
US3763405A (en) 1970-12-21 1973-10-02 Nippon Electric Co Solid state luminescent display device
US3875456A (en) 1972-04-04 1975-04-01 Hitachi Ltd Multi-color semiconductor lamp
US4729076A (en) 1984-11-15 1988-03-01 Tsuzawa Masami Signal light unit having heat dissipating function
DE3632743A1 (en) 1986-09-26 1988-03-31 Standard Elektrik Lorenz Ag Optical waveguide with a microlens at the end
US5187765A (en) 1991-07-23 1993-02-16 Fostec, Inc. Backlighted panel
US5208462A (en) 1991-12-19 1993-05-04 Allied-Signal Inc. Wide bandwidth solid state optical source
US5461547A (en) 1993-07-20 1995-10-24 Precision Lamp, Inc. Flat panel display lighting system
US5477430A (en) 1995-03-14 1995-12-19 Delco Electronics Corporation Fluorescing keypad
US5499138A (en) 1992-05-26 1996-03-12 Olympus Optical Co., Ltd. Image display apparatus
US5535230A (en) 1994-04-06 1996-07-09 Shogo Tzuzuki Illuminating light source device using semiconductor laser element
US5622423A (en) 1995-10-09 1997-04-22 Lee; Hang-Bok Hand-carried traffic control light
US5777433A (en) 1996-07-11 1998-07-07 Hewlett-Packard Company High refractive index package material and a light emitting device encapsulated with such material
US5808409A (en) 1993-12-17 1998-09-15 Kabushiki Kaisha Toshiba Phosphor, cathode-ray tube, fluorescent lamp and radiation intensifying screen
US5813752A (en) 1997-05-27 1998-09-29 Philips Electronics North America Corporation UV/blue LED-phosphor device with short wave pass, long wave pass band pass and peroit filters
US5813753A (en) 1997-05-27 1998-09-29 Philips Electronics North America Corporation UV/blue led-phosphor device with efficient conversion of UV/blues light to visible light
US5847507A (en) 1997-07-14 1998-12-08 Hewlett-Packard Company Fluorescent dye added to epoxy of light emitting diode lens
US5959316A (en) 1998-09-01 1999-09-28 Hewlett-Packard Company Multiple encapsulation of phosphor-LED devices
US5962971A (en) 1997-08-29 1999-10-05 Chen; Hsing LED structure with ultraviolet-light emission chip and multilayered resins to generate various colored lights
US5998925A (en) 1996-07-29 1999-12-07 Nichia Kagaku Kogyo Kabushiki Kaisha Light emitting device having a nitride compound semiconductor and a phosphor containing a garnet fluorescent material
US6007209A (en) 1997-03-19 1999-12-28 Teledyne Industries, Inc. Light source for backlighting
US6066861A (en) 1996-09-20 2000-05-23 Siemens Aktiengesellschaft Wavelength-converting casting composition and its use
US6068383A (en) 1998-03-02 2000-05-30 Robertson; Roger Phosphorous fluorescent light assembly excited by light emitting diodes
US6084250A (en) 1997-03-03 2000-07-04 U.S. Philips Corporation White light emitting diode
US6096496A (en) 1997-06-19 2000-08-01 Frankel; Robert D. Supports incorporating vertical cavity emitting lasers and tracking apparatus for use in combinatorial synthesis
US6155699A (en) 1999-03-15 2000-12-05 Agilent Technologies, Inc. Efficient phosphor-conversion led structure
US6210012B1 (en) 1998-03-27 2001-04-03 U.S. Philips Corporation Backlight system and display device comprising such a system
WO2001040702A1 (en) 1999-12-03 2001-06-07 Cree Lighting Company Solid state lamp
US6252254B1 (en) 1998-02-06 2001-06-26 General Electric Company Light emitting device with phosphor composition
JP2001243807A (en) 2000-02-28 2001-09-07 Mitsubishi Electric Lighting Corp Led electric bulb
JP2001243821A (en) 2000-02-28 2001-09-07 Mitsubishi Electric Lighting Corp Surface light source with led
US6294800B1 (en) 1998-02-06 2001-09-25 General Electric Company Phosphors for white light generation from UV emitting diodes
US20020003233A1 (en) 1999-09-27 2002-01-10 Mueller-Mach Regina B. Light emitting diode (LED) device that produces white light by performing phosphor conversion on all of the primary radiation emitted by the light emitting structure of the LED device
US20020030444A1 (en) 1999-09-27 2002-03-14 Regina B. Muller-Mach Thin film phosphor-converted light emitting diode device
US6357889B1 (en) 1999-12-01 2002-03-19 General Electric Company Color tunable light source
US20020047516A1 (en) 2000-10-24 2002-04-25 Tadanobu Iwasa Fluorescent tube
US20020084745A1 (en) 2000-12-29 2002-07-04 Airma Optoelectronics Corporation Light emitting diode with light conversion by dielectric phosphor powder
US6452217B1 (en) 2000-06-30 2002-09-17 General Electric Company High power LED lamp structure using phase change cooling enhancements for LED lighting products
JP2002299694A (en) 2001-03-29 2002-10-11 Mitsubishi Electric Lighting Corp Led light-source device for illumination and illuminator
US6469322B1 (en) 1998-02-06 2002-10-22 General Electric Company Green emitting phosphor for use in UV light emitting diodes
US20020167014A1 (en) 1999-11-03 2002-11-14 Karl-Heinz Schlereth LED white light source with broadband excitation
US6483196B1 (en) 2000-04-03 2002-11-19 General Electric Company Flip chip led apparatus
US6491412B1 (en) 1999-09-30 2002-12-10 Everbrite, Inc. LED display
US6513949B1 (en) 1999-12-02 2003-02-04 Koninklijke Philips Electronics N.V. LED/phosphor-LED hybrid lighting systems
US20030030060A1 (en) 2001-08-07 2003-02-13 Tadahiro Okazaki White semiconductor light-emitting device
US6576930B2 (en) 1996-06-26 2003-06-10 Osram Opto Semiconductors Gmbh Light-radiating semiconductor component with a luminescence conversion element
US6576935B2 (en) 2000-07-12 2003-06-10 Fuji Electric Co., Ltd. Bidirectional semiconductor device and method of manufacturing the same
US6580224B2 (en) 2000-06-05 2003-06-17 Kabushiki Kaisha Toshiba Backlight for color liquid crystal, color liquid crystal display device, and EL element for backlight of color liquid crystal device
US6580097B1 (en) 1998-02-06 2003-06-17 General Electric Company Light emitting device with phosphor composition
US20030127660A1 (en) 1998-04-01 2003-07-10 Bawendi Moungi G. Quantum dot white and colored light emitting diodes
US6600175B1 (en) 1996-03-26 2003-07-29 Advanced Technology Materials, Inc. Solid state white light emitter and display using same
US6603258B1 (en) 2000-04-24 2003-08-05 Lumileds Lighting, U.S. Llc Light emitting diode device that emits white light
US6608332B2 (en) 1996-07-29 2003-08-19 Nichia Kagaku Kogyo Kabushiki Kaisha Light emitting device and display
US6616862B2 (en) 2001-05-21 2003-09-09 General Electric Company Yellow light-emitting halophosphate phosphors and light sources incorporating the same
US20030174499A1 (en) 2002-03-14 2003-09-18 Bohlander Richard A. LED light source
US6630691B1 (en) 1999-09-27 2003-10-07 Lumileds Lighting U.S., Llc Light emitting diode device comprising a luminescent substrate that performs phosphor conversion
US20030189829A1 (en) 2001-08-09 2003-10-09 Matsushita Electric Industrial Co., Ltd. LED illumination apparatus and card-type LED illumination source
US6635363B1 (en) 2000-08-21 2003-10-21 General Electric Company Phosphor coating with self-adjusting distance from LED chip
US6635987B1 (en) 2000-09-26 2003-10-21 General Electric Company High power white LED lamp structure using unique phosphor application for LED lighting products
US20030203524A1 (en) 2001-03-09 2003-10-30 Faramarz Farahi Process for packaging of light emitting devices using a spin-on-glass material
US20030201451A1 (en) 2002-04-05 2003-10-30 Toyoda Gosei Co., Ltd. Light emitting diode
US6653765B1 (en) 2000-04-17 2003-11-25 General Electric Company Uniform angular light distribution from LEDs
US20030218880A1 (en) 2001-12-31 2003-11-27 Brukilacchio Thomas J. Led white light optical system
EP1369935A1 (en) 2002-06-07 2003-12-10 Lumileds Lighting US, LLC Light-emitting devices utilizing nanoparticles
US20030230751A1 (en) 2002-05-31 2003-12-18 Stanley Electric Co., Ltd. Light-emitting device and manufacturing method thereof
US6686676B2 (en) 2001-04-30 2004-02-03 General Electric Company UV reflectors and UV-based light sources having reduced UV radiation leakage incorporating the same
US6686691B1 (en) 1999-09-27 2004-02-03 Lumileds Lighting, U.S., Llc Tri-color, white light LED lamps
US20040027062A1 (en) 2001-01-16 2004-02-12 General Electric Company Organic electroluminescent device with a ceramic output coupler and method of making the same
JP2004055229A (en) 2002-07-17 2004-02-19 Mitsubishi Electric Lighting Corp Led lighting system and lighting equipment
JP2004055160A (en) 2002-07-16 2004-02-19 Mitsubishi Electric Lighting Corp Led light source device
US20040056260A1 (en) 2002-09-19 2004-03-25 Slater David B. Phosphor-coated light emitting diodes including tapered sidewalls, and fabrication methods therefor
US20040116033A1 (en) 2003-01-27 2004-06-17 3M Innovative Properties Company Methods of making phosphor based light sources having an interference reflector
US20040124758A1 (en) 2000-07-28 2004-07-01 Osram Opto Semiconductors Gmbh Luminescene conversion based light emitting diode and phosphors for wave length conversion
US20040129945A1 (en) 2002-07-25 2004-07-08 Toyoda Gosei Co., Ltd. Light emitting apparatus
DE10261428A1 (en) 2002-12-30 2004-07-22 Osram Opto Semiconductors Gmbh Radiation emitting semiconductor element with semiconductor body having number of layers in the radiation direction useful in semiconductor technology
US6791259B1 (en) 1998-11-30 2004-09-14 General Electric Company Solid state illumination system containing a light emitting diode, a light scattering material and a luminescent material
US6793374B2 (en) 1998-09-17 2004-09-21 Simon H. A. Begemann LED lamp
US6799865B2 (en) 2001-07-31 2004-10-05 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH LED-based planar light source
US20040203312A1 (en) 2000-08-07 2004-10-14 Bortscheller Jacob C. LED cross-linkable phosphor coating
US20040208210A1 (en) 2003-04-01 2004-10-21 Sharp Kabushiki Kaisha Light-emitting apparatus package, light-emitting apparatus, backlight apparatus, and display apparatus
US20040217364A1 (en) 2003-05-01 2004-11-04 Cree Lighting Company, Inc. Multiple component solid state white light
US20040233664A1 (en) 2003-05-23 2004-11-25 Beeson Karl W. Illumination systems utilizing multiple wavelength light recycling
US20040245912A1 (en) 2003-04-01 2004-12-09 Innovalight Phosphor materials and illumination devices made therefrom
US6833565B2 (en) 2002-12-20 2004-12-21 Industrial Technology Research Institute White-light led with dielectric omni-directional reflectors
US20040263073A1 (en) 2003-06-27 2004-12-30 Baroky Tajul Arosh White light emitting device
US20040263074A1 (en) 2003-06-27 2004-12-30 Baroky Tajul Arosh White light emitting device
US20050041424A1 (en) 1999-11-18 2005-02-24 Color Kinetics, Inc. Systems and methods for converting illumination
US6867542B1 (en) 2000-03-29 2005-03-15 General Electric Company Floating chip photonic device and method of manufacture
US20050073495A1 (en) 2003-10-03 2005-04-07 Gerard Harbers LCD backlight using two-dimensional array LEDs
US20050093430A1 (en) 2003-02-26 2005-05-05 Cree, Inc. Composite white light source and method for fabricating
US20050117366A1 (en) 2003-12-02 2005-06-02 Simbal John J. Reflective light coupler
US20050117125A1 (en) 2003-11-14 2005-06-02 Light Prescriptions Innovators, Llc Dichroic beam combiner utilizing blue LED with green phosphor
US20050116635A1 (en) 2003-12-02 2005-06-02 Walson James E. Multiple LED source and method for assembling same
EP1160883A3 (en) 2000-05-31 2005-06-22 Matsushita Electric Industrial Co., Ltd. LED lamp
US20050135079A1 (en) 2003-12-18 2005-06-23 Yin Chua Janet B. Flash module with quantum dot light conversion
US20050135117A1 (en) 2003-12-23 2005-06-23 Lamb David J. Hybrid lightguide backlight
US20050162849A1 (en) 2004-01-26 2005-07-28 Lumileds Lighting U.S., Llc LED with an optical system to increase luminance by recycling emitted light
US20050174775A1 (en) 2004-02-11 2005-08-11 3M Innovative Properties Company Light-collecting illumination system
US20050185419A1 (en) 2003-01-24 2005-08-25 Digital Optics International Corporation High-density illumination system
US6936857B2 (en) 2003-02-18 2005-08-30 Gelcore, Llc White light LED device
US20050211991A1 (en) 2004-03-26 2005-09-29 Kyocera Corporation Light-emitting apparatus and illuminating apparatus
US20050219476A1 (en) 2004-03-30 2005-10-06 Beeson Karl W Projection display systems utilizing light emitting diodes and light recycling
US20050237488A1 (en) 2004-04-22 2005-10-27 Futoshi Yamasaki Image display apparatus
US20050248958A1 (en) 2001-08-23 2005-11-10 Li Kenneth K LED illumination engine using a reflector
US20050265029A1 (en) 2004-06-01 2005-12-01 3M Innovative Properties Company Led array systems
US20050276553A1 (en) 2001-08-31 2005-12-15 Smith & Nephew, Inc., A Delaware Corporation Solid-state light source
US20050280785A1 (en) 2004-06-16 2005-12-22 Beeson Karl W Projection display systems utilizing color scrolling and light emitting diodes
US20060002141A1 (en) 2004-06-30 2006-01-05 Ouderkirk Andrew J Phosphor based illumination system having a short pass reflector and method of making same
US20060007553A1 (en) 2002-09-30 2006-01-12 Georg Bogner Device for producing a bundled light flux
US20060034082A1 (en) 2004-08-12 2006-02-16 Samsung Electro-Mechanics Co., Ltd. Multi-lens light emitting diode
US20060034084A1 (en) 2004-06-28 2006-02-16 Kyocera Corporation Light-emitting apparatus and illuminating apparatus
US7002291B2 (en) 2000-05-29 2006-02-21 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh LED-based white-emitting illumination unit
US20060044523A1 (en) 2002-11-07 2006-03-02 Teijido Juan M Illumination arrangement for a projection system
US20060044803A1 (en) 2004-09-02 2006-03-02 Custom Interconnect Ltd. LED light source
US20060067078A1 (en) 2004-09-28 2006-03-30 Goldeneye, Inc. Light recycling illumination systems having restricted angular output
US20060066192A1 (en) 2004-09-28 2006-03-30 Goldeneye, Inc Light recycling illumination systems utilizing light emiting diodes
US20060066210A1 (en) * 2004-09-30 2006-03-30 Ng Kee Y Light source with wavelength converting material
US20060071225A1 (en) 2004-09-28 2006-04-06 Goldeneye, Inc Light emitting diodes exhibiting both high reflectivity and high light extraction
US20060072314A1 (en) 2004-09-29 2006-04-06 Advanced Optical Technologies, Llc Optical system using LED coupled with phosphor-doped reflective materials
US7026656B2 (en) 2004-05-07 2006-04-11 Lite-On Technology Corporation White light-emitting device
US20060081862A1 (en) 2004-10-14 2006-04-20 Chua Janet B Y Device and method for emitting output light using quantum dots and non-quantum fluorescent material
US20060091788A1 (en) 2004-10-29 2006-05-04 Ledengin, Inc. Light emitting device with a thermal insulating and refractive index matching material
US20060097385A1 (en) 2004-10-25 2006-05-11 Negley Gerald H Solid metal block semiconductor light emitting device mounting substrates and packages including cavities and heat sinks, and methods of packaging same
US20060104090A1 (en) 2004-11-12 2006-05-18 Harris Corporation LED light engine for backlighting a liquid crystal display
US7049740B2 (en) 2001-10-09 2006-05-23 Avago Technologies, Ltd. Light emitting diode
US20060118805A1 (en) 2003-07-31 2006-06-08 Camras Michael D Light emitting devices with improved light extraction efficiency
EP1686630A2 (en) 2005-01-31 2006-08-02 Samsung Electronics Co., Ltd. Led device having diffuse reflective surface
US20060170335A1 (en) 2005-01-31 2006-08-03 Samsung Electronics Co., Ltd. LED device having diffuse reflective surface
US20060186429A1 (en) 2005-02-22 2006-08-24 Chew Tong F Semiconductor light emitting device and method of manufacture
EP1696496A1 (en) 2005-02-25 2006-08-30 SuperNova Optoelectronics Corporation Light emitting device
US20060202219A1 (en) 2005-03-09 2006-09-14 Kabushiki Kaisha Toshiba Semiconductor light emitting device and semiconductor light emitting apparatus
US7192161B1 (en) 2001-10-18 2007-03-20 Ilight Technologies, Inc. Fluorescent illumination device
EP1691425A4 (en) 2003-11-25 2007-09-26 Matsushita Electric Works Ltd Light emitting device using light emitting diode chip
US20080231170A1 (en) * 2004-01-26 2008-09-25 Fukudome Masato Wavelength Converter, Light-Emitting Device, Method of Producing Wavelength Converter and Method of Producing Light-Emitting Device
US20080310158A1 (en) 2007-06-18 2008-12-18 Xicato, Inc. Solid State Illumination Device
US7498734B2 (en) 2003-06-18 2009-03-03 Toyoda Gosei Co., Ltd. Light emitting device with wavelength converted by phosphor

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6538371B1 (en) * 2000-03-27 2003-03-25 The General Electric Company White light illumination system with improved color output
TW474115B (en) * 2000-11-07 2002-01-21 Helix Technology Inc Manufacturing method of organic light emitting diode
JP2003110146A (en) * 2001-07-26 2003-04-11 Matsushita Electric Works Ltd Light-emitting device
KR100894372B1 (en) * 2001-10-01 2009-04-22 파나소닉 주식회사 Semiconductor light emitting element and light emitting device using this
JP2004031843A (en) * 2002-06-28 2004-01-29 Kyocera Corp Light-emitting diode
JP4197109B2 (en) * 2002-08-06 2008-12-17 静雄 藤田 Lighting device
US7139389B2 (en) * 2002-08-06 2006-11-21 Daniel Neal Duncan System and method for allocating contact resources to contact resource users
JP2004083653A (en) * 2002-08-23 2004-03-18 Sharp Corp Light emitting device, phosphor and method for producing the same
JP4504662B2 (en) * 2003-04-09 2010-07-14 シチズン電子株式会社 LED lamp
JP2005019981A (en) * 2003-06-05 2005-01-20 Matsushita Electric Ind Co Ltd Fluorescent material, semiconductor light-emitting element and method of fabricating these
JP2005013006A (en) * 2003-06-23 2005-01-20 Washi Kosan Co Ltd Complex food inhibiting energy metabolism of overnutrition
JP5456233B2 (en) * 2003-06-24 2014-03-26 ジーイー ライティング ソリューションズ エルエルシー Full spectrum phosphor mixture for white light generation by LED chip
US7195161B2 (en) * 2003-09-18 2007-03-27 The Directv Group, Inc. Smart card reader
JP2005136006A (en) * 2003-10-28 2005-05-26 Matsushita Electric Works Ltd Light-emitting device and producing device using it
JP4285198B2 (en) * 2003-10-28 2009-06-24 パナソニック電工株式会社 Light emitting device
JP2005159045A (en) * 2003-11-26 2005-06-16 Sumitomo Electric Ind Ltd Semiconductor light emitting element mounting member and light emitting diode using the same
JP2005228996A (en) * 2004-02-13 2005-08-25 Matsushita Electric Works Ltd Light-emitting device
CN101138104B (en) * 2005-06-23 2011-08-24 伦斯勒工业学院 Package design for producing white light with short-wavelength leds and down-conversion materials

Patent Citations (155)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3593055A (en) 1969-04-16 1971-07-13 Bell Telephone Labor Inc Electro-luminescent device
US3763405A (en) 1970-12-21 1973-10-02 Nippon Electric Co Solid state luminescent display device
US3875456A (en) 1972-04-04 1975-04-01 Hitachi Ltd Multi-color semiconductor lamp
US3760237A (en) 1972-06-21 1973-09-18 Gen Electric Solid state lamp assembly having conical light director
US4729076A (en) 1984-11-15 1988-03-01 Tsuzawa Masami Signal light unit having heat dissipating function
DE3632743A1 (en) 1986-09-26 1988-03-31 Standard Elektrik Lorenz Ag Optical waveguide with a microlens at the end
US5187765A (en) 1991-07-23 1993-02-16 Fostec, Inc. Backlighted panel
US5208462A (en) 1991-12-19 1993-05-04 Allied-Signal Inc. Wide bandwidth solid state optical source
US5499138A (en) 1992-05-26 1996-03-12 Olympus Optical Co., Ltd. Image display apparatus
US5461547A (en) 1993-07-20 1995-10-24 Precision Lamp, Inc. Flat panel display lighting system
US5808409A (en) 1993-12-17 1998-09-15 Kabushiki Kaisha Toshiba Phosphor, cathode-ray tube, fluorescent lamp and radiation intensifying screen
US5535230A (en) 1994-04-06 1996-07-09 Shogo Tzuzuki Illuminating light source device using semiconductor laser element
US5477430A (en) 1995-03-14 1995-12-19 Delco Electronics Corporation Fluorescing keypad
US5622423A (en) 1995-10-09 1997-04-22 Lee; Hang-Bok Hand-carried traffic control light
US20060049416A1 (en) 1996-03-26 2006-03-09 Bruce Baretz Solid state white light emitter and display using same
US6600175B1 (en) 1996-03-26 2003-07-29 Advanced Technology Materials, Inc. Solid state white light emitter and display using same
US20040016938A1 (en) 1996-03-26 2004-01-29 Bruce Baretz Solid state white light emitter and display using same
US6576930B2 (en) 1996-06-26 2003-06-10 Osram Opto Semiconductors Gmbh Light-radiating semiconductor component with a luminescence conversion element
US5777433A (en) 1996-07-11 1998-07-07 Hewlett-Packard Company High refractive index package material and a light emitting device encapsulated with such material
US6614179B1 (en) 1996-07-29 2003-09-02 Nichia Kagaku Kogyo Kabushiki Kaisha Light emitting device with blue light LED and phosphor components
US5998925A (en) 1996-07-29 1999-12-07 Nichia Kagaku Kogyo Kabushiki Kaisha Light emitting device having a nitride compound semiconductor and a phosphor containing a garnet fluorescent material
US6608332B2 (en) 1996-07-29 2003-08-19 Nichia Kagaku Kogyo Kabushiki Kaisha Light emitting device and display
US6069440A (en) 1996-07-29 2000-05-30 Nichia Kagaku Kogyo Kabushiki Kaisha Light emitting device having a nitride compound semiconductor and a phosphor containing a garnet fluorescent material
US6066861A (en) 1996-09-20 2000-05-23 Siemens Aktiengesellschaft Wavelength-converting casting composition and its use
US6245259B1 (en) 1996-09-20 2001-06-12 Osram Opto Semiconductors, Gmbh & Co. Ohg Wavelength-converting casting composition and light-emitting semiconductor component
US6084250A (en) 1997-03-03 2000-07-04 U.S. Philips Corporation White light emitting diode
US6007209A (en) 1997-03-19 1999-12-28 Teledyne Industries, Inc. Light source for backlighting
US5813753A (en) 1997-05-27 1998-09-29 Philips Electronics North America Corporation UV/blue led-phosphor device with efficient conversion of UV/blues light to visible light
US5813752A (en) 1997-05-27 1998-09-29 Philips Electronics North America Corporation UV/blue LED-phosphor device with short wave pass, long wave pass band pass and peroit filters
US6096496A (en) 1997-06-19 2000-08-01 Frankel; Robert D. Supports incorporating vertical cavity emitting lasers and tracking apparatus for use in combinatorial synthesis
US5847507A (en) 1997-07-14 1998-12-08 Hewlett-Packard Company Fluorescent dye added to epoxy of light emitting diode lens
US5962971A (en) 1997-08-29 1999-10-05 Chen; Hsing LED structure with ultraviolet-light emission chip and multilayered resins to generate various colored lights
US6580097B1 (en) 1998-02-06 2003-06-17 General Electric Company Light emitting device with phosphor composition
US6252254B1 (en) 1998-02-06 2001-06-26 General Electric Company Light emitting device with phosphor composition
US6294800B1 (en) 1998-02-06 2001-09-25 General Electric Company Phosphors for white light generation from UV emitting diodes
US6469322B1 (en) 1998-02-06 2002-10-22 General Electric Company Green emitting phosphor for use in UV light emitting diodes
US6068383A (en) 1998-03-02 2000-05-30 Robertson; Roger Phosphorous fluorescent light assembly excited by light emitting diodes
US6210012B1 (en) 1998-03-27 2001-04-03 U.S. Philips Corporation Backlight system and display device comprising such a system
US20030127660A1 (en) 1998-04-01 2003-07-10 Bawendi Moungi G. Quantum dot white and colored light emitting diodes
US5959316A (en) 1998-09-01 1999-09-28 Hewlett-Packard Company Multiple encapsulation of phosphor-LED devices
US6793374B2 (en) 1998-09-17 2004-09-21 Simon H. A. Begemann LED lamp
US6791259B1 (en) 1998-11-30 2004-09-14 General Electric Company Solid state illumination system containing a light emitting diode, a light scattering material and a luminescent material
US6155699A (en) 1999-03-15 2000-12-05 Agilent Technologies, Inc. Efficient phosphor-conversion led structure
US6630691B1 (en) 1999-09-27 2003-10-07 Lumileds Lighting U.S., Llc Light emitting diode device comprising a luminescent substrate that performs phosphor conversion
US6696703B2 (en) 1999-09-27 2004-02-24 Lumileds Lighting U.S., Llc Thin film phosphor-converted light emitting diode device
US6686691B1 (en) 1999-09-27 2004-02-03 Lumileds Lighting, U.S., Llc Tri-color, white light LED lamps
US6501102B2 (en) 1999-09-27 2002-12-31 Lumileds Lighting, U.S., Llc Light emitting diode (LED) device that produces white light by performing phosphor conversion on all of the primary radiation emitted by the light emitting structure of the LED device
US20020003233A1 (en) 1999-09-27 2002-01-10 Mueller-Mach Regina B. Light emitting diode (LED) device that produces white light by performing phosphor conversion on all of the primary radiation emitted by the light emitting structure of the LED device
US20020030444A1 (en) 1999-09-27 2002-03-14 Regina B. Muller-Mach Thin film phosphor-converted light emitting diode device
US6491412B1 (en) 1999-09-30 2002-12-10 Everbrite, Inc. LED display
US20020167014A1 (en) 1999-11-03 2002-11-14 Karl-Heinz Schlereth LED white light source with broadband excitation
US6734467B2 (en) 1999-11-03 2004-05-11 Osram Opto Semiconductors Gmbh & Co. Ohg LED white light source with broadband excitation
US20050041424A1 (en) 1999-11-18 2005-02-24 Color Kinetics, Inc. Systems and methods for converting illumination
US6357889B1 (en) 1999-12-01 2002-03-19 General Electric Company Color tunable light source
US6692136B2 (en) 1999-12-02 2004-02-17 Koninklijke Philips Electronics N.V. LED/phosphor-LED hybrid lighting systems
US6513949B1 (en) 1999-12-02 2003-02-04 Koninklijke Philips Electronics N.V. LED/phosphor-LED hybrid lighting systems
US20030067773A1 (en) 1999-12-02 2003-04-10 Koninklijke Philips Electronics N.V. LED/phosphor-LED hybrid lighting systems
WO2001040702A1 (en) 1999-12-03 2001-06-07 Cree Lighting Company Solid state lamp
US6350041B1 (en) 1999-12-03 2002-02-26 Cree Lighting Company High output radial dispersing lamp using a solid state light source
JP2001243807A (en) 2000-02-28 2001-09-07 Mitsubishi Electric Lighting Corp Led electric bulb
JP2001243821A (en) 2000-02-28 2001-09-07 Mitsubishi Electric Lighting Corp Surface light source with led
US6867542B1 (en) 2000-03-29 2005-03-15 General Electric Company Floating chip photonic device and method of manufacture
US6483196B1 (en) 2000-04-03 2002-11-19 General Electric Company Flip chip led apparatus
US6653765B1 (en) 2000-04-17 2003-11-25 General Electric Company Uniform angular light distribution from LEDs
US6603258B1 (en) 2000-04-24 2003-08-05 Lumileds Lighting, U.S. Llc Light emitting diode device that emits white light
US7002291B2 (en) 2000-05-29 2006-02-21 Patent-Treuhand-Gesellschaft Fur Elektrische Gluhlampen Mbh LED-based white-emitting illumination unit
EP1160883A3 (en) 2000-05-31 2005-06-22 Matsushita Electric Industrial Co., Ltd. LED lamp
US6580224B2 (en) 2000-06-05 2003-06-17 Kabushiki Kaisha Toshiba Backlight for color liquid crystal, color liquid crystal display device, and EL element for backlight of color liquid crystal device
US6452217B1 (en) 2000-06-30 2002-09-17 General Electric Company High power LED lamp structure using phase change cooling enhancements for LED lighting products
US6576935B2 (en) 2000-07-12 2003-06-10 Fuji Electric Co., Ltd. Bidirectional semiconductor device and method of manufacturing the same
US20040124758A1 (en) 2000-07-28 2004-07-01 Osram Opto Semiconductors Gmbh Luminescene conversion based light emitting diode and phosphors for wave length conversion
US20040203312A1 (en) 2000-08-07 2004-10-14 Bortscheller Jacob C. LED cross-linkable phosphor coating
US6635363B1 (en) 2000-08-21 2003-10-21 General Electric Company Phosphor coating with self-adjusting distance from LED chip
US6635987B1 (en) 2000-09-26 2003-10-21 General Electric Company High power white LED lamp structure using unique phosphor application for LED lighting products
US20020047516A1 (en) 2000-10-24 2002-04-25 Tadanobu Iwasa Fluorescent tube
US20020084745A1 (en) 2000-12-29 2002-07-04 Airma Optoelectronics Corporation Light emitting diode with light conversion by dielectric phosphor powder
US6614170B2 (en) 2000-12-29 2003-09-02 Arima Optoelectronics Corporation Light emitting diode with light conversion using scattering optical media
US20040027062A1 (en) 2001-01-16 2004-02-12 General Electric Company Organic electroluminescent device with a ceramic output coupler and method of making the same
US20030203524A1 (en) 2001-03-09 2003-10-30 Faramarz Farahi Process for packaging of light emitting devices using a spin-on-glass material
JP2002299694A (en) 2001-03-29 2002-10-11 Mitsubishi Electric Lighting Corp Led light-source device for illumination and illuminator
US6686676B2 (en) 2001-04-30 2004-02-03 General Electric Company UV reflectors and UV-based light sources having reduced UV radiation leakage incorporating the same
US6616862B2 (en) 2001-05-21 2003-09-09 General Electric Company Yellow light-emitting halophosphate phosphors and light sources incorporating the same
US6799865B2 (en) 2001-07-31 2004-10-05 Patent-Treuhand-Gesellschaft für elektrische Glühlampen mbH LED-based planar light source
US20030030060A1 (en) 2001-08-07 2003-02-13 Tadahiro Okazaki White semiconductor light-emitting device
US20030189829A1 (en) 2001-08-09 2003-10-09 Matsushita Electric Industrial Co., Ltd. LED illumination apparatus and card-type LED illumination source
US20050248958A1 (en) 2001-08-23 2005-11-10 Li Kenneth K LED illumination engine using a reflector
US20050276553A1 (en) 2001-08-31 2005-12-15 Smith & Nephew, Inc., A Delaware Corporation Solid-state light source
US7049740B2 (en) 2001-10-09 2006-05-23 Avago Technologies, Ltd. Light emitting diode
US7192161B1 (en) 2001-10-18 2007-03-20 Ilight Technologies, Inc. Fluorescent illumination device
US20030218880A1 (en) 2001-12-31 2003-11-27 Brukilacchio Thomas J. Led white light optical system
US6796690B2 (en) 2002-03-14 2004-09-28 The Boeing Company LED light source
US20030174499A1 (en) 2002-03-14 2003-09-18 Bohlander Richard A. LED light source
US20030201451A1 (en) 2002-04-05 2003-10-30 Toyoda Gosei Co., Ltd. Light emitting diode
US20030230751A1 (en) 2002-05-31 2003-12-18 Stanley Electric Co., Ltd. Light-emitting device and manufacturing method thereof
US6809342B2 (en) 2002-05-31 2004-10-26 Stanley Electric Co., Ltd. Light-emitting device and manufacturing method thereof
US20030227249A1 (en) * 2002-06-07 2003-12-11 Lumileds Lighting, U.S., Llc Light-emitting devices utilizing nanoparticles
EP1369935A1 (en) 2002-06-07 2003-12-10 Lumileds Lighting US, LLC Light-emitting devices utilizing nanoparticles
JP2004055160A (en) 2002-07-16 2004-02-19 Mitsubishi Electric Lighting Corp Led light source device
JP2004055229A (en) 2002-07-17 2004-02-19 Mitsubishi Electric Lighting Corp Led lighting system and lighting equipment
US20040129945A1 (en) 2002-07-25 2004-07-08 Toyoda Gosei Co., Ltd. Light emitting apparatus
US20040056260A1 (en) 2002-09-19 2004-03-25 Slater David B. Phosphor-coated light emitting diodes including tapered sidewalls, and fabrication methods therefor
US20060007553A1 (en) 2002-09-30 2006-01-12 Georg Bogner Device for producing a bundled light flux
US20060044523A1 (en) 2002-11-07 2006-03-02 Teijido Juan M Illumination arrangement for a projection system
US6833565B2 (en) 2002-12-20 2004-12-21 Industrial Technology Research Institute White-light led with dielectric omni-directional reflectors
DE10261428A1 (en) 2002-12-30 2004-07-22 Osram Opto Semiconductors Gmbh Radiation emitting semiconductor element with semiconductor body having number of layers in the radiation direction useful in semiconductor technology
US20050185419A1 (en) 2003-01-24 2005-08-25 Digital Optics International Corporation High-density illumination system
US20040116033A1 (en) 2003-01-27 2004-06-17 3M Innovative Properties Company Methods of making phosphor based light sources having an interference reflector
US6936857B2 (en) 2003-02-18 2005-08-30 Gelcore, Llc White light LED device
US20050093430A1 (en) 2003-02-26 2005-05-05 Cree, Inc. Composite white light source and method for fabricating
US20040245912A1 (en) 2003-04-01 2004-12-09 Innovalight Phosphor materials and illumination devices made therefrom
US20040208210A1 (en) 2003-04-01 2004-10-21 Sharp Kabushiki Kaisha Light-emitting apparatus package, light-emitting apparatus, backlight apparatus, and display apparatus
US20040217364A1 (en) 2003-05-01 2004-11-04 Cree Lighting Company, Inc. Multiple component solid state white light
US20040233664A1 (en) 2003-05-23 2004-11-25 Beeson Karl W. Illumination systems utilizing multiple wavelength light recycling
US7040774B2 (en) 2003-05-23 2006-05-09 Goldeneye, Inc. Illumination systems utilizing multiple wavelength light recycling
US7498734B2 (en) 2003-06-18 2009-03-03 Toyoda Gosei Co., Ltd. Light emitting device with wavelength converted by phosphor
US20040263073A1 (en) 2003-06-27 2004-12-30 Baroky Tajul Arosh White light emitting device
US20040263074A1 (en) 2003-06-27 2004-12-30 Baroky Tajul Arosh White light emitting device
US20060118805A1 (en) 2003-07-31 2006-06-08 Camras Michael D Light emitting devices with improved light extraction efficiency
US20050073495A1 (en) 2003-10-03 2005-04-07 Gerard Harbers LCD backlight using two-dimensional array LEDs
US7052152B2 (en) 2003-10-03 2006-05-30 Philips Lumileds Lighting Company, Llc LCD backlight using two-dimensional array LEDs
US20050117125A1 (en) 2003-11-14 2005-06-02 Light Prescriptions Innovators, Llc Dichroic beam combiner utilizing blue LED with green phosphor
EP1691425A4 (en) 2003-11-25 2007-09-26 Matsushita Electric Works Ltd Light emitting device using light emitting diode chip
US20050117366A1 (en) 2003-12-02 2005-06-02 Simbal John J. Reflective light coupler
US20050116635A1 (en) 2003-12-02 2005-06-02 Walson James E. Multiple LED source and method for assembling same
US20050135079A1 (en) 2003-12-18 2005-06-23 Yin Chua Janet B. Flash module with quantum dot light conversion
US20050135117A1 (en) 2003-12-23 2005-06-23 Lamb David J. Hybrid lightguide backlight
US20080231170A1 (en) * 2004-01-26 2008-09-25 Fukudome Masato Wavelength Converter, Light-Emitting Device, Method of Producing Wavelength Converter and Method of Producing Light-Emitting Device
US20050162849A1 (en) 2004-01-26 2005-07-28 Lumileds Lighting U.S., Llc LED with an optical system to increase luminance by recycling emitted light
US20050174775A1 (en) 2004-02-11 2005-08-11 3M Innovative Properties Company Light-collecting illumination system
US20050211991A1 (en) 2004-03-26 2005-09-29 Kyocera Corporation Light-emitting apparatus and illuminating apparatus
US20050219476A1 (en) 2004-03-30 2005-10-06 Beeson Karl W Projection display systems utilizing light emitting diodes and light recycling
US20050237488A1 (en) 2004-04-22 2005-10-27 Futoshi Yamasaki Image display apparatus
US7026656B2 (en) 2004-05-07 2006-04-11 Lite-On Technology Corporation White light-emitting device
US20050265029A1 (en) 2004-06-01 2005-12-01 3M Innovative Properties Company Led array systems
US20050280785A1 (en) 2004-06-16 2005-12-22 Beeson Karl W Projection display systems utilizing color scrolling and light emitting diodes
US7048385B2 (en) 2004-06-16 2006-05-23 Goldeneye, Inc. Projection display systems utilizing color scrolling and light emitting diodes
US20060034084A1 (en) 2004-06-28 2006-02-16 Kyocera Corporation Light-emitting apparatus and illuminating apparatus
US20060002141A1 (en) 2004-06-30 2006-01-05 Ouderkirk Andrew J Phosphor based illumination system having a short pass reflector and method of making same
US20060034082A1 (en) 2004-08-12 2006-02-16 Samsung Electro-Mechanics Co., Ltd. Multi-lens light emitting diode
US20060044803A1 (en) 2004-09-02 2006-03-02 Custom Interconnect Ltd. LED light source
US20060066192A1 (en) 2004-09-28 2006-03-30 Goldeneye, Inc Light recycling illumination systems utilizing light emiting diodes
US20060067078A1 (en) 2004-09-28 2006-03-30 Goldeneye, Inc. Light recycling illumination systems having restricted angular output
US20060071225A1 (en) 2004-09-28 2006-04-06 Goldeneye, Inc Light emitting diodes exhibiting both high reflectivity and high light extraction
US20060072314A1 (en) 2004-09-29 2006-04-06 Advanced Optical Technologies, Llc Optical system using LED coupled with phosphor-doped reflective materials
US20060066210A1 (en) * 2004-09-30 2006-03-30 Ng Kee Y Light source with wavelength converting material
US20060081862A1 (en) 2004-10-14 2006-04-20 Chua Janet B Y Device and method for emitting output light using quantum dots and non-quantum fluorescent material
US20060097385A1 (en) 2004-10-25 2006-05-11 Negley Gerald H Solid metal block semiconductor light emitting device mounting substrates and packages including cavities and heat sinks, and methods of packaging same
US20060091788A1 (en) 2004-10-29 2006-05-04 Ledengin, Inc. Light emitting device with a thermal insulating and refractive index matching material
US20060104090A1 (en) 2004-11-12 2006-05-18 Harris Corporation LED light engine for backlighting a liquid crystal display
US20060170335A1 (en) 2005-01-31 2006-08-03 Samsung Electronics Co., Ltd. LED device having diffuse reflective surface
EP1686630A2 (en) 2005-01-31 2006-08-02 Samsung Electronics Co., Ltd. Led device having diffuse reflective surface
US20060186429A1 (en) 2005-02-22 2006-08-24 Chew Tong F Semiconductor light emitting device and method of manufacture
EP1696496A1 (en) 2005-02-25 2006-08-30 SuperNova Optoelectronics Corporation Light emitting device
US20060202219A1 (en) 2005-03-09 2006-09-14 Kabushiki Kaisha Toshiba Semiconductor light emitting device and semiconductor light emitting apparatus
US20080310158A1 (en) 2007-06-18 2008-12-18 Xicato, Inc. Solid State Illumination Device

Non-Patent Citations (28)

* Cited by examiner, † Cited by third party
Title
Akos Borbely, et al., Prediction of Light Extraction Efficiency of LEDs by Ray Trace Simulation, Third International Conference on Solid State Lighting, Proc. Of SPIE vol. 5187, pp. 301-308 (2004)*.
Chen et al., InGaN-CdSe-ZnSe Quantum Dots White LEDs, IEEE Photonics Technology Letters IEEE USA, vol. 18, No. 1, Jan. 2006, pp. 193-195.
D.A. Vanderwater et al., High-Brightness AlGaInP Light Emitting Diodes, Proceedings of the IEE, vol. 85, No. 11, Nov. 1997, pp. 1752-1764.
English language translation of the Third Office Action in Chinese Patent Application No. 200580022283.9 mailed on Jan. 22, 2010.
European Office Action in EP Application No. 05 761 021.4 dated Oct. 8, 2009.
European Search Report of Application No. EP 05 76 1021 dated Jun. 18, 2008.
First Office Action for Chinese Application No. 2005800222839 dated Jul. 8, 2008 (including English translation).
International Search Report for PCT International Application No. PCT/US05/15736 mailed Mar. 30, 2006.
International Search Report for PCT International Application No. PCT/US2006/024210 mailed Oct. 12, 2006.
International Search Report of PCT International Application No. PCT/US2005/015736 dated Mar. 30, 2006 (3 pages).
Kenichi Yamada et al., Optical Simulation of Light Source Devices Composed of Blue LEDs and YAG Phosphor, J. Light & Vis. Env. vol. 27, No. 2, 2003, pp. 70-74.
Kim J.K. et al: "Strongly Enhanced Phosphor Efficiency in GaInN White Light-Emitting Diodes Using Remote Phosphor configuration and Diffuse Reflector Cup" Japanese Journal of Applied Physics, Part 2 (Letters) Japan Soc. Appl. Phys Japan, vol. 44, No. 21, 2005, pp. L649-L651.
Krames M.R. et al.: "High-power III-nitride emitters for solid-state lighting" Phys. Stat. sol. (a) Wiley-VCH Verlag Berlin GmbH, Berlin, vol. 192, No. 2 (2002) pp. 237-245.
M. Arik et al., Effects of Localized Heat Generations Due to the Color Conversion in Phosphor Particles and Layers of High Brightness Light Emitting Diodes, American Society of Mechanical Engineers (ASME), Proceedings of InterPACK '03, International Electronic Packaging Technical Conference and Exhibition, Maui, Hawaii, Jul. 2003, pp. 1-9, title page, copyright page and abstract page.
N. Narendran et al., Solid-state Lighting: failure analysis of white LEDs, Journal of Crystal Growth, 268 (2004) pp. 449-456.
Search Report for International Application Serial No. PCT/US2007/013132 dated Dec. 3, 2007.
Search Report for International Application Serial No. PCT/US2007/013132 dated Jan. 31, 2008.
Search Report from International Application Serial No. PCT/US2007/012311 dated Feb. 15, 2008.
Song Jae Lee, Study of Photon Extraction Efficiency in InGaN Light-Emitting Diodes Depending on Chip Structures and Chip-Mount Schemes, Optical Engineering, Jan. 2006, vol. 45(1), pp. 014601-1-014601-14.
United States Patent and Trademark Office Office Action for U.S. Appl. No. 11/642,089 dated Mar. 10, 2009.
United States Patent and Trademark Office Office Action for U.S. Appl. No. 11/642,089 dated May 28, 2008.
United States Patent and Trademark Office Office Action for U.S. Appl. No. 11/642,154 dated Sep. 25, 2008.
United States Patent and Trademark Office Office Action in U.S. Appl. No. 10/583,105 dated Jun. 19, 2009.
United States Patent and Trademark Office Office Action in U.S. Appl. No. 11/642,154 dated Jun. 2, 2009.
United States Patent and Trademark Office Office Action of U.S. Appl. No. 10/583,105 dated Nov. 4, 2008.
USPTO Office Action in U.S. Appl. No. 11/642,089 dated Jul. 23, 2009.
USPTO Office Action in U.S. Appl. No. 11/644,815 dated Feb. 3, 2009.
USPTO Office Action in U.S. Appl. No. 11/644,815 dated Sep. 18, 2009.

Cited By (52)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8067254B2 (en) * 2004-11-12 2011-11-29 Philips Lumileds Lighting Company Llc Common optical element for an array of phosphor converted light emitting devices
US20100109568A1 (en) * 2004-11-12 2010-05-06 Koninklijke Philips Electronics N.V. Common optical element for an array of phosphor converted llight emitting devices
US9220149B2 (en) * 2006-01-20 2015-12-22 Cree, Inc. Lighting devices having remote lumiphors that are excited by lumiphor-converted semiconductor excitation sources
US20130241392A1 (en) * 2006-01-20 2013-09-19 Cree, Inc. Lighting devices having remote lumiphors that are excited by lumiphor-converted semiconductor excitation sources
US20090268461A1 (en) * 2008-04-28 2009-10-29 Deak David G Photon energy conversion structure
US9140844B2 (en) 2008-05-06 2015-09-22 Qd Vision, Inc. Optical components, systems including an optical component, and devices
US9946004B2 (en) 2008-05-06 2018-04-17 Samsung Electronics Co., Ltd. Lighting systems and devices including same
US10627561B2 (en) 2008-05-06 2020-04-21 Samsung Electronics Co., Ltd. Lighting systems and devices including same
US10359555B2 (en) 2008-05-06 2019-07-23 Samsung Electronics Co., Ltd. Lighting systems and devices including same
US9167659B2 (en) * 2008-05-06 2015-10-20 Qd Vision, Inc. Solid state lighting devices including quantum confined semiconductor nanoparticles, an optical component for a solid state lighting device, and methods
US10145539B2 (en) 2008-05-06 2018-12-04 Samsung Electronics Co., Ltd. Solid state lighting devices including quantum confined semiconductor nanoparticles, an optical component for a solid state lighting device, and methods
US9207385B2 (en) 2008-05-06 2015-12-08 Qd Vision, Inc. Lighting systems and devices including same
US20110103064A1 (en) * 2008-05-06 2011-05-05 Seth Coe-Sullivan Solid state lighting devices including quantum confined semiconductor nanoparticles, an optical component for a solid state lighting device, and methods
US8227979B2 (en) * 2008-12-04 2012-07-24 Samsung Electronics Co., Ltd. Method of matching color in lighting applications
US20100144231A1 (en) * 2008-12-04 2010-06-10 Daniel Landry Method of matching color in lighting applications
US9466757B2 (en) 2009-04-28 2016-10-11 Qd Vision, Inc. Optical materials, optical components, devices, and methods
US9133388B2 (en) 2009-04-28 2015-09-15 Qd Vision, Inc. Optical materials, optical components, and methods
US9905724B2 (en) 2009-04-28 2018-02-27 Samsung Electronics Co., Ltd. Optical materials, optical components, and methods
US9391244B2 (en) 2009-08-14 2016-07-12 Qd Vision, Inc. Lighting devices, an optical component for a lighting device, and methods
US8981339B2 (en) 2009-08-14 2015-03-17 Qd Vision, Inc. Lighting devices, an optical component for a lighting device, and methods
US9134459B2 (en) 2009-10-17 2015-09-15 Qd Vision, Inc. Optical component, products including same, and methods for making same
US9605833B2 (en) 2009-10-17 2017-03-28 Samsung Electronics Co., Ltd. Optical component, products including same, and methods for making same
US20110164430A1 (en) * 2010-01-07 2011-07-07 Kenneth Li Illuminator using light emitting diode light recycling with collimation
US8965148B2 (en) * 2010-04-27 2015-02-24 Osram Opto Semiconductors Gmbh Optoelectronic component and method for producing an optoelectronic component
US20130039617A1 (en) * 2010-04-27 2013-02-14 Stefan Illek Optoelectronic Component and Method for Producing an Optoelectronic Component
US9562671B2 (en) 2010-08-20 2017-02-07 Research Triangle Institute Color-tunable lighting devices and methods of use
US9101036B2 (en) 2010-08-20 2015-08-04 Research Triangle Institute Photoluminescent nanofiber composites, methods for fabrication, and related lighting devices
US9441811B2 (en) 2010-08-20 2016-09-13 Research Triangle Institute Lighting devices utilizing optical waveguides and remote light converters, and related methods
US10158057B2 (en) 2010-10-28 2018-12-18 Corning Incorporated LED lighting devices
US20130016499A1 (en) * 2010-12-28 2013-01-17 Young Joo Yee Optical device and light emitting diode package using the same, and backlight apparatus
US20120217865A1 (en) * 2011-02-25 2012-08-30 Cree, Inc. Solid state light emitting devices including nonhomogeneous luminophoric particle size layers
US8742654B2 (en) * 2011-02-25 2014-06-03 Cree, Inc. Solid state light emitting devices including nonhomogeneous luminophoric particle size layers
US9412905B2 (en) * 2011-04-01 2016-08-09 Najing Technology Corporation Limited White light emitting device
US20140022779A1 (en) * 2011-04-01 2014-01-23 Kai Su White light emitting device
US8957438B2 (en) 2011-04-07 2015-02-17 Cree, Inc. Methods of fabricating light emitting devices including multiple sequenced luminophoric layers
US20130043786A1 (en) * 2011-08-19 2013-02-21 Epistar Corporation Wavelength conversion structure, manufacturing method thereof, and light-emitting device comprising the wavelength conversion structure
US8853937B2 (en) * 2011-08-19 2014-10-07 Epistar Corporation Wavelength conversion structure, manufacturing method thereof, and light-emitting device comprising the wavelength conversion structure
US8687882B2 (en) * 2011-12-23 2014-04-01 Blackberry Limited Apparatus, and associated method, for facilitating white balancing of an image
US20130163866A1 (en) * 2011-12-23 2013-06-27 Research In Motion Limited Apparatus, and associated method, for facilitating white balancing of an image
US9261244B2 (en) * 2012-02-02 2016-02-16 Flextronics Automoive GmbH & Co. KG LED lamp with layered light modifying element
US20140009929A1 (en) * 2012-02-02 2014-01-09 Flextronics Automotive Gmbh & Co Kg Lamp with a translucent plastic element
US20150083933A1 (en) * 2013-09-25 2015-03-26 Phoseon Technology, Inc. Multi-wavelength led curing lamp
US9318649B2 (en) * 2013-09-25 2016-04-19 Phoseon Technology, Inc. Multi-wavelength LED curing lamp
US9423551B2 (en) 2014-03-10 2016-08-23 Samsung Display Co., Ltd. Backlight assembly and display apparatus having the same
US20150362643A1 (en) * 2014-06-11 2015-12-17 Hitachi Maxell, Ltd. Diffractive lens and optical device using the same
US9915764B2 (en) * 2014-06-11 2018-03-13 Hitachi Maxell, Ltd. Diffractive lens and optical device using the same
US20170005239A1 (en) * 2015-06-30 2017-01-05 Nichia Corporation Light emitting device
US9735323B2 (en) * 2015-06-30 2017-08-15 Nichia Corporation Light emitting device having a triple phosphor fluorescent member
US11043618B2 (en) 2015-11-02 2021-06-22 Nanoco Technologies Ltd. Display devices comprising green-emitting quantum dots and red KSF phosphor
US9905735B1 (en) * 2017-03-31 2018-02-27 Cree, Inc. High brightness, low-cri semiconductor light emitting devices including narrow-spectrum luminescent materials
US10818827B2 (en) 2017-09-28 2020-10-27 Nichia Corporation Light-emitting device
US11605761B2 (en) 2017-09-28 2023-03-14 Nichia Corporation Light-emitting device

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